Summer is well and truly here in Okinawa, with the temperatures rising and the sun shining. Checked the weather report at 9am this morning and was told that it was 31°C but that it felt “like 36°C”. Thankfully the humidity was only 70% and a sea breeze coming through my apartment managed to keep me [...]
It’s been a long time coming, but I drove my 1991 FC3S RX-7 home today from the garage after being inspected and registered. Yes, I am finally road legal and ready to roll. You’ve got to love Okinawa: maybe the only place in Japan where cracked tyres and stuck brakes don’t cause a fail in the shakken!
Took it to my garage last Wednesday after managing to pick up some temporary licence plates (which I must remember to return tomorrow after work). That was a nervy drive; my tuning shop is about 15km away and it was the first time I’d driven it any distance at all. Was nervously watching the gauges and trying to get used to the car. I wasn’t driving fast by any means but a RWD car and a rotary engine’d one at that will take some getting used to. But it got there in one piece and I left it with them for the inspection and to register it.
And I got the call yesterday that it was ready to rock and roll, and had passed the shakken. What I was told though was that the rear brakes are stuck about 20% on. I’ve jacked the car up and you can still turn the rear wheels but there is some definite resistance there. Hopefully if there’s any corrosion I will be able to clean it off with emery cloth or similar and new seals should do it. Worst case would probably just be that I need new sliders and/or a brake piston for the rear. Will find that out on Saturday when I do some work on it. But I’ve got new pads (Endless) and rotors (Dixcel) for all 4 corners. With those, caliper seal rebuild kits and some new brake fluid I should be good to go.
As you can see, I’ve also picked up a new O2 sensor. Think that after 20 years this one probably has its best days behind it, and a replacement for these is always good. And I’ve got some 16″ Dunlop Star Spec tyres on order from the States, which should be coming in any day now. The tyres I’ve got on mine are marginal at best, and I really need replacements. Not going to spend much on upgrading this car (mainly as I don’t have that much disposable income these days), but I’m not going to skimp on brakes and tyres. Star Specs are probably the best “bang-per-buck” tyres you can get at the moment and they’re not too expensive either.
So providing all goes well on Saturday and I get the tyres in, it will be all ready for some testing out. I’m going to treat the car like it’s got a brand new engine for the first few hundred kilometres (i.e. baby it generally). If anything is going to go on the car due to it being rotten or worn out, it will be that first tank or 2 of petrol, and I’d rather not be flying around a corner if something does give way. Should give big props once again to Speed Factory for getting my car road legal, Steve, Josh and anyone else I’ve missed for helping me out. Am actually pretty stoked though as it looks like I’ve managed to bring this car back from the dead and get it into a somewhat decent condition. Maybe even cause for a drink or 2…
Apologies for the godawful attempt at a play on words in the title. It’s almost 1am and it’s all I could think of so please forgive me. Thought it was time I gave you an update seeing as my last post talked about me throwing a firework into the engine of my car “for testing purposes”. Wanted to reassure/disappoint you all by letting you know that I still live. That little event was not without incident though, as you will see.
So to recap, I was pretty sure my 1991 Mazda RX-7 had a vacuum leak which was causing the surging idle. People kept saying the engine might have a cracked apex seal but I wasn’t buying that as the last time it was compression checked it was all ok. So I decided to get a “smoke bomb” firework and put it into the intake manifold of my car so the smoke would flow around and I could see where it came out of. You’re all thinking “Darwin Awards” already, but to bear with me! Went to the shops and found some fireworks that I needed from the Y100 shop. Bought them and excitedly went home. First plan was to put the firework just before the throttle body and then stick a long lighter in there and light it from a distance. That didn’t go exactly to plan, as you can see.
Yeah, that’s what happens when a lighter, petrol and air mix together. You’re lucky my digital camera doesn’t have sound or you’ll have heard my scream followed by letting an expletive or two out! So I went upstairs, had a stiff drink and revised my plan. Next idea was to light the smoke bomb first, and then once it was smoking to put it into the throttle body. While this didn’t nearly set me on fire, it didn’t really have the effect I was looking for. In fact, the only effect it had was making it look like I’d powdercoated the insider of my throttle body and intake manifold!
I was hitting a wall pretty hard and not really knowing where to go. The car seemed like it would drive well enough, but that idle would most likely prevent it from getting a shaken (the Japanese car inspection certificate). And it wouldn’t make for the most enjoyable driving experience in the world. Once again I took the upper intake manifold and throttle body off and had another look at it. After cleaning both of smoke bomb remnants, I found something interesting with the throttle body. Take a look below and see if you can spot the problem:
See it? What we have here are 3 throttle plates. The top one is fine and is supposed to have a hole in it (the car has to get some air when idling so that it will keep running). The issue is the bottom 2 plates. They are partially open but should be completely closed. This means that the throttle sensor will be sending a signal to the ECU saying that the engine is at idle, and a given predetermined airflow is entering the engine. But in reality those plates being open means that the actual volume of air in the engine is higher than that. This was causing the engine to go searching for a correct fuel/air mix and getting all confused, hence the fluctuating idle. I took the throttle body apart, cleaned it up and did a bit of adjusting so that the bottom plates were closed, and then refitted it all. I also removed a cold-start cam that I’d forgotten to pull when I previously took out the cold start system. Attached everything and tentatively turned the key.
The engine fired as normal and died after a couple of seconds, but I got a different feeling with it. There was no high idle before it died and no misfiring; it was just as if the idle was set too low. I played around with the idle screw and tried again. The engine fired up and started idling perfectly at 800rpm, with no surging, no misfiring, and no signs of problems. I could rev it and it would come straight back to a perfect idle.
And here I am, at a point where the car is idling right and fingers crossed it will drive well soon. So all that remains is for me to get the car booked in for an inspection and to do what I can to it to make sure it passes. Will report back with how it’s gone very soon, but it’s a huge boost to have come this far. I bought a car which wouldn’t start at all, and have got it starting reliably, troubleshooted high & surging idles, and now have it where I think it is fully driveable. Whether that’s the case, only time will tell…
I think after all this working on my car, I am just a boost/vacuum leak away from it running right. I used an air tank and a boost leak checker contraption last night. Fitted it up to my turbo and pressurized the system to about 0.6bar. When I turned the air off the system lost pressure within a couple of seconds, with an audible noise. I then tried hooking it straight up to the throttle body (I wanted to bypass the intercooler and piping to rule that out) and pressurised it again. Got the same result with the noise coming from somewhere on the driver’s side of the intake manifold area. Tried spraying soapy water over it all but couldn’t see any bubbles.
That’s got to be what’s causing my strange idle though. I’m sure when I work it out the idle will come down to what it should be and will hold steady there. Have just got to find out where the leak’s coming from. It could very well be a vacuum line somewhere that’s not connected and should be, or that is connected somewhere where it shouldn’t. Someone else guessed at the gasket between upper and lower intake manifolds, but I replaced the gasket on that a couple of months ago when I first started messing with the engine so it shouldn’t be that.
To lose 0.6bar of pressure in a couple of seconds would constitute a pretty big leak so I’ve had a couple of suggestions of sending smoke into the intake manifold and seeing if I can see where it’s coming out of. Unfortunately I don’t seem to be able to find any “smoke pellets” here in Okinawa. But I am actually considering buying a “smoke bomb” firework and sticking that into my throttle body after lighting it. I mean, what’s the worst that could happen?!
So if you never hear from me again after this post, well I’ve probably gone up in smoke in southern Japan! This volcanic ash cloud is gonna have nothing on my troubleshooting my car! Will leave you with a few pics of me working on my car, and one of the neighbour’s kid in front of it, who always comes down to offer encouragement whenever she hears me cursing under my breath.
The old adage that “No news is good news” doesn’t really apply here. Work is continuing on the RX-7 but am not getting much closer to sorting out this wavering idle just yet. I’ve checked out the throttle position sensor (which is well known for going wrong) but that is right in spec and adjusted where it needs to be. But the idle still starts off being high and then just wavers between 1000 and 1500rpm, surging every second or 2. My next guess would be a vacuum leak and so I’ve bought a vacuum/boost leak tester to pressurize the system and check it out. Am really hoping I get some big leaks which would explain why I’m having issues.
To be honest, the car is probably drivable now, or rather will be as soon as I raise the front end of the suspension so it can actually get out of my parking area! And in fact I may take it out this weekend and just take it down the street and back, sans licence plates. I just want to make sure it will move ok and get into 2nd gear etc. But it’s just a tiny bit off the point where I want to fork out the money for registration, shaken, and insurance for it. Last Saturday I ordered some front indicator lenses and side light bulb holders, and I got a call today saying they’ve come in today. Will be picking them up tomorrow and fitting them, which should make my front end look a little more complete.
Back onto the mechanical side and I also found out the reason my boost gauge on the dash wasn’t working is because the boost pressure sensor seems to be dead. Voltages were way out of spec and so I’m going to be picking up another one to test tomorrow. The question I want to be answered is what the boost sensor actually does on the car. It could be that it just controls the boost gauge but it might be that it actually has an influence on the fuelling and ignition, through the ECU. That might just be wishful thinking but replacing this COULD sort out my idling issues.
Only time will tell but I’ll let you know when I find out.
What an absolute mission that headgasket replacement was! Started it at about 9:45 on Wednesday morning and finished up at about 4:15am on Thursday morning, and that’s with no real stops for food or drinks. Although to be honest, from 11am to about 5:30pm we were stuck in a certain spot and trying different was of getting around it.
So, met up with my buddy just after 9am and we grabbed breakfast before heading straight to work on it. The plan was to get the head off the engine, replace the headgasket & valve cover seals, put it back together and be done by nightfall. By the looks of it, the valve cover gaskets were leaking pretty badly, and the spark plugs were virtually swimming with oil. Am sure it’s not great for engine performance! But Suzuki designed the twin-cam valve covers so that if you wanted to remove a single valve cover, the timing belt had to come off. Awesome! So we started up and was going pretty well to begin with. No major dramas in getting the accessory belts and coolant lines off that go around the timing belt cover. We were going to try and lift the head off while keeping the timing belt in situ so we wouldn’t have to bother with removing the crankshaft pulley. But then we realized that Suzuki, in their infinite mechanical wisdom, decided that it would be a good idea to have a single cambelt cover for their twin-cam F6A engine (as opposed to the top & bottom covers for many of the single cam models). Have no idea why they made it like this but they must have had some amazing idea in mind. What it did was make life for us pretty frustrating.
Looked like we’d just have to pull the crankshaft pulley off and then the timing belt cover would come off all in one, but that is much easier said than done. The crank pulleys on these are notoriously hard to get loose, and because of where the engine’s positioned in the engine bay, there is pretty much no room to work in. We did get a breaker bar on it. with a metal pipe for extra leverage. I put it in 5th gear and held the break down while torque was applied but it just wasn’t budging. We tried a little impact, but you can’t really impact on it where it’s positioned.
We even headed out to a tool shop and picked up a wrench that grips onto the pulley so it won’t slip (can’t remember exactly what it’s called though) and we managed to break that by applying too much torque to it. So we came to the conclusion that the only way we were going to be able to get the crank pulley bolt off was to use impact, and the only was we could get an angle to get impact was with the engine out of the car.
So for the next hour or 2 we removed a bunch of other stuff in the way, as well as the motor mounts (the rear one of which is in a ludicrous place – well done once again Suzuki) and the tranny mounts. By very late afternoon we’d almost got to the point where we could lift the engine out of the car. But now we had two other problems:
1. How the hell do we get the halfshafts out of the as we lifted the whole shebang up?
2. The garages would be closed soon and it’s possibly many would be closed tomorrow and for the next few days for the new year’s break.
Removing the engine was tuning into a bit of a bad idea. So we took another look at the timing belt cover and then we (alright, my buddy) had a minor stroke of genius idea. We both agreed the timing belt cover should be in 2 parts, so why not cut it into 2 parts! Cue getting a hacksaw blade out and cutting into the plastic timing belt cover just above the timing marks next to the crank pulley. We had to cut it low so we could get to the timing belt tensioner if needs be, and at the same timing, hoping the blade didn’t slip and start cutting into the timing belt (which would have given us no option but to take the whole engine out.
After a short while though we’d cut the cover in 2 and it had turned out pretty well. We marked up the timing belt on both cam gears as well as on the crankshaft, and then pulled off the cam gears themselves. To be honest, from that point onwards it was relatively straightforward. When we pulled the cam covers off it was clear that one of the seals at the end was leaking oil, and will have to be replaced in the near future once Suzuki is open again and I can get the parts ordered.
The head was next to come off and the pistons looked in remarkably good shape considering they had done over 140,000km. The gasket itself looked in ok condition too, as well as the surface of both head and block. It was all cleaned and new headgasket and rocker cover gaskets replaced and torqued back up to spec. The timing belt took a few tries to get right as we were cheating a little by keeping the timing belt over the crank pulley sprocket at the bottom, so it was a little tough to get everything lined up and in sync. But we did it and after connecting everything back up the engine fired up at the first attempt.
It was idling smoothly although there was a definite tapping sound which didn’t sound amazing. After a little while that went away though and we attributed it to being that we’d cleaned and re-greased the lifters. Soon it was sounding back to normal (read “like a sewing machine on heat”). By the time we’d cleaned up and I was ready to leave it was past 4am but it was a job relatively well done, and if we were taking the head off again, I reckon it could be done and replaced in about 3-4 hours.
A couple of minor downsides. While we seem to have sorted out one oil leak, the one at the crankshaft side of the engine is still there. Would be willing to put money on it being that camseal that had failed that is the source of the oil leak. That will have to get sorted out just as soon as Suzuki reopens after the new year and I can get the seals ordered. And the leak in the spark plug area turned out to not be from the rocker cover seals, but from the 3-4cm long rubber hoses that go from one rocker cover to the other. Have put new clamps on the hoses but it’s not had a huge effect. When I replace the rocker cover seals I’ll put new hoses on them which will hopefully seal much better.
So big thanks to Mike for helping me out with this one. There are more pictures and at a higher resolution over in my gallery, so have a look if you have a few minutes.
“What’s the best way to break in a new engine?” This is a question I’ve been asking myself over the past few weeks and opinions on breaking-in or running-in an engine is a topic of huge debate. People often sit in one camp and will rarely listen to the opinions of others and accept that they may be as good or even better than their own. In the next couple of articles I’d like to cover a couple of methods of breaking in an engine, which will maybe give you some ideas if you are in the process of doing an engine rebuild. This first method I will describe is the method I am currently using to break-in my 4G63-based Evo I.
The first few steps seem to be common among all the theories, and involve putting in cheap mineral oil into the engine, along with a cheap oil filter. This is partly because they will be replaced very quickly, and partly because mineral oil offers a little more friction which will be useful as the car starts. You want to prime the oil system first, either by spinning the oil pump sprocket with a drill with the timing belt off, or turning the starter with the fuel and ignition disabled. This will get oil pressure into the system which will help get things lubricated and running smoothly as soon as the engine starts.
The engine is then fired up and allowed to warm up for 20-30 minutes. While it’s warming up you’ll want to keep the radiator cap off and keep an eye on coolant levels/check for oil leaks/fuel leaks etc. As it’s up to working temperature you’ll also want to take a timing light to the engine and set the base timing (5 degrees for the early Evos). Once the oil and engine are up to speed then turn off the engine, change the oil to your regular synthetic and change oil filter too. This is because in the engine assembly there will have been contaminants covering a lot of the parts. 20-30 minutes of the engine running should have got these contaminants either suspended in the oil or caught up in the oil filter.
Right, with fresh oil in the engine the fun can begin. The important thing to remember during the break-in is not to go too easy on the car, especially in the vital 60-100 miles. There is a good chance if you do that the cylinder walls will glaze and the piston rings will never get a good seal. In decades gone by people were told to be very gentle on their cars for the first thousand or so miles, but this was so that parts which may have been badly machined could be rubbing against each other and you wanted to reduce their friction as much as possible. These days, if parts are rubbing against each other then you already have a big problem. So I am trying to keep my revs above 2,000rpm.
With regards to driving, I’m doing a lot of high throttle/low boost runs from idle up to anywhere from 2-5,000rpm. I’m hitting a maximum of about 0.7bar of boost during this time. When I hit the top rpm I want to reach I won’t brake or upshift; I’ll just take my foot off the accelerator and let engine braking slow the car right down to idle speed again. This supposedly helps the piston rings seat themselves which will obviously help in the long-run. The only other thing to be wary of is travelling too much on the expressway at a constant speed. That won’t really do much for the engine in these important early miles.
I’m planning to follow this path for around 4-500 miles and then have a good tuning session on the car and start to put my foot down! It’s pretty difficult at the moment as just as the car starts to wake up I have to get off the throttle, but the break-in is not something you want to rush. Any thoughts on the way I’m going about it, either good or bad?
A bit of a how-to for you folks out there with an early Evo (and also 1G/2G DSM). There aren’t too many guides on how to bleed/change brake fluid on these cars alone and, although the procedures are fairly similar between cars, a specific guide is also helpful. I will write up a 2-man version in the near future, but the one-man procedure is very simple to follow. Don’t want to be condescending in this guide but I’m going to try and explain everything as simply as I can. I want this guide to be as user-friendly as possible.
Your brake system is an enclosed system but it can get air bubbles in it sometimes, and through hard braking the brake fluid can boil, causing it to become much less effective. I would recommend bleeding or indeed flushing the whole system every 6 to 12 months. I will give instructions on how to bleed the system, and then give some additional info about flushing the system at the end. Brake fluid is also hydroscopic, which means it absolutely loves water and absorbs it, making it much less effective. For this reason, when you put new brake fluid into the system it is much better to use fluid straight out of an unopened container. Additionally, it’s best not to do this procedure when it’s raining or damp.
Right, onto business. First thing are the things you need for this, and fortunately you don’t need any specialist tools. But you will need the following:
Wheel brace (my wheel nuts are 21mm but yours may be different. Most likely you have this already)
Jack
10mm wrench
60cm of rubber tubing, 5mm inside diameter and preferably see-through
Small container (a old jar or something will do)
Brake fluid, DOT 4 or DOT 5.1 if you are a big-spender
With all those things ready, let’s get to it.
And that’s all there is to it! The next wheel you should jack up is the driver’s side front, followed by the driver’s side rear, and finally the passenger side front. When you’ve done all four, make sure the brake fluid reservoir is filled up to the max level on the side and the top is screwed on securely.
So that’s the procedure for bleeding the brakes. In order to flush the system, it’s an almost identical procedure. Just bleed an entire reservoir of fluid through the system for each brake. Once again, make sure the reservoir is never completely empty. For this you’ll probably need 1-1.5l of brake fluid.
I think that covers everything. If this has helped you or you have any questions, do let me know. Will try to write more of these guides if people tell me what they want to read.
If you ask someone in Japan what is the worst thing about car ownership in Japan you will probably get a mixture of responses. “Drunken old guys driving into you”, “road surfaces being made partly from coral and offering no grip” and, “the accident insurance system where you are almost always held to partial blame for an accident for existing (friend hit side-on by a Japanese guy in a carpark has been told that they expect him to pay 50% of the costs to repair his own car; if he hadn’t have been in the carpark the accident would never have happened” are just three of them. But maybe the most common complaint people will have is something called the shaken, or JCI (Japanese Compulsory Insurance) for those US servicemembers and families with SOFA status.
Almost every developed country has some system of ensuring cars are roadworthy. In the UK they have the annual MOT – a comprehensive check of the vehicle to make sure it is safe to be on the road. Well here in Japan we have the shaken, which is conducted on all vehicles every 2 years. The testing process appears similar to that of the UK, although probably not quite as detailed. Some of the things it checks are sensible (working headlights, exhaust emissions etc), and some are not. The car, for example, must have some way of telling the driver which position the gearstick must be in for each particular gear in a manual transmission car. Stock gearknobs have this but if you have an aftermarket gearknob then you have to get a sticker somewhere visible in the interior, seemingly in case you forget where all your gears are and need a diagram to help you out (hint: if this applies to you then please stay at home or use public transport!).
But it’s not the testing criteria that most people take issue with. In fact, even a lot of tuner’s cars pass the shaken relatively easily, and I think mine will pass without any problems providing I re-install the cat and get that all-important gear sticker. But the biggest problem is the cost. As I mentioned in a previous post, I am expecting my shaken fee in a couple of months to come to at least Y50,000 (about 300 quid) and probably closer to Y70,000 (500 quid), and that’s providing nothing needs repairing or changing. Jay from over at Newzjapan commented that his shaken is likely to cost around Y120,000 (just over 850 quid). Wikipedia has the cost broken down as follows: Y25,500 for the testing fee, Y29,780 for 2 years of validity (yup, I’m not sure what that means either), Y8,090 to be given to the recycling department, and then an additional fee depending on who your mechanic is, what your car is and probably the phase of the moon or something like that. Let us just compare that firstly to the US, where the same car would cost about Y11,000 to test (around 80 quid) and in the UK an MOT test costs Y7,400 (just over 50 quid). Yes… as you can see the difference is not insignificant. But everyone just accepts the cost because they know that here if they speak up they will have a lonely voice as acceptance is the most popular policy.
When you tell people outside of Japan the test cost they automatically assume that is going through a car dealership, and that an independent garage fee would be much cheaper. The reality is that the costs I am quoting come from independent garages in Okinawa (which probably has the cheapest prices for things like this in all of Japan). A dealership fee for something like this is likely to be even higher. Maybe you are starting to see why public transport is so favourable in mainland Japan (where it actually functions adequately). It is possible for you to go to the car inspection centre and test the car yourself but the cost you will save is nominal and it’s a lot of hassle so people don’t really do it and leave it to their mechanic.
So while Japan does have some good points for motoring (stock parts at decent prices, good quality aftermarket parts, reasonably priced petrol), there are one or two things that crop up that really put a proverbial spanner in the works. I’ve got my shaken coming up in March which I’m not looking forward to financially, although it should be a simple pass through for the test itself. Should probably make some witty pun about being “shaken but not stirred”, but I would never stoop to that kind of level!
Loading ...