Re: 1992 Typhoon 0546 rebuild
I’ve had 10 days off after my second term exams so spent my time doing a few jobs. First on the list was the lower IC fan wiring which I connected via a stock relay. By doing the IC pump hotwire, I freed up an ECM controlled ground and this operates the relay so even when the car is stationary, I have airflow over the lower IC. I have one for now but may even try for another someday. The installation is very similar to a stock setup so I am very pleased with the result.
I had big plans to get the truck ready for an MOT and then a dyno but I was met with a plethora of problems. First was the fuel pump – for some reason it died but after giving the truck some new petrol and powering it on and off, it came back to life. I am quite impulsive and on first sighting of a problem, I order a spare. Better to need it that not though right? The new pump arrived but I think the old one is ok. I’ll keep the spare for the time being. They’re common to Mitsubishis and other Japanese cars so freely available in the UK for about £55 if you’re looking.
However, on start, the car sounded like an absolute bucket of bolts. It was horrendous. I thought I had a damaged crank or the pistons were dropping onto the floor of the garage but the car hasn’t been driven so it couldn’t have been that. I had high oil pressure (50psi) so I tore off the valve covers and tried adjusting the valves but they kept on compressing, rattling and throwing off the compression settings. I made the decision to tear down the engine and replace all the hydraulic lifters. This slowed me down so I set about doing some other jobs that have been on the back burner.
Some of you may be aware that the steering can feel a bit sloppy. One of the repair options is to replace a bearing at the firewall. Originally there is a white plastic cup which the shaft rotates at the pint where the shaft enters the column. This can wear down and allow movement into the assembly.
I took out the old piece and replaced it with a new design which made the column extremely firm. I have now done everything possible to the front steering. The only other potential upgrade is a rack and pinion setup. It should feel pretty good when (if) I get it roadworthy again. While I was in there I wire brushed the collar and spray painted it black so it looks good. Now I need to do the rest of the column housing!
I have the Jeep steering shaft and took it off to gain access to the collar/bearing and noticed that the bolts holding it in are the wrong kind. I had some spare shiny ARP 16 point bolts so installed them as they were the correct fit. They make the shaft look a bit rubbish though so I am not sure what I should do to bring it up to the same standard.
The Jeep shaft places the wheel at 90* to right of centre so I rekeyed the steering locking plate to the correct angle. This involved a 30 second job with a file. I also installed a lock plate retaining ring which is basically a small key ring sized clip that holds the locking plate in place.
The steering column is now very firm, locks securely and releases easily as well. Seeing as I have had to install the ring, replace the bearing and also replace the lock barrel mechanism, I should hope so! It’s starting to feel like a different truck.
My lifters were due to arrive from the USA on Wednesday morning via FedEx so I got to work first thing. I had the engine stripped down to the lower intake in about 2 hours and started cleaning off all the gasket material and prepping for the install. Just as I finished, the FedEx man arrived and handed me the goods. I opened up the box and inserted the lifters into some oil while I prepped the gaskets.
I’ve done this before and one of the things I didn’t like was the way that the gaskets can slide so this time I applied the RTV permatex black ultra to the gasket and then applied the gasket to the lower intake, making sure that the holes were all lined up. Normally I apply the RTV to the heads, then the gaskets, then the lower intake. This time however, there was a lot less mess, I know the gaskets were placed optimally and it went together smoothly. I cranked down the bolts and started building the engine back up. I had it reassembled by about 6pm and started trying to start it. The truck started but it needed a LOT of throttle and was spluttering and backfiring. Aside from a 10 minute tea break, I’d been in the garage for 10 hours by this point and was starting to make mistakes so I called it a night.
The following morning, I started investigating the backfiring which initially I took for a spark. I could see a flash of light and though a cable was shorting out. On closer inspection it turned out I was looking directly into the crossover pipe and was seeing unburnt fuel in the crossover exploding. Something was amiss so I checked everything over again and found #3 and #5 were swapped. After I changed them over, the truck ran much better! I now know that I need to adjust the crossover pipe as well but that shouldn’t be too bad.
It wasn’t quite right still so I did a compression check on all the cylinders. This has caught me out in the past so when I got 120 psi on all cylinders, I was a bit disappointed and slightly worried. Memories of Marcus’ blown headgasket ran through my head – I was convinced at one point that I had the same problem. Thankfully I had documented my efforts last summer and I had 165psi on all the cylinders. I don’t think it’s possible to blow a headgasket without the engine running so I started adjusting the lifters on each cylinder and doing a compression check, one cylinder at a time.
Turn crank, get up, check for TDC/BDC, get down, turn crank to TDC, get up, adjust 1 valve, do comp test. Repeat if necessary, or move on x 12!!! This took me quite a while but in the end I had about 155, 155, 150, 170 and 155psi on 1, 2, 3, 4 and 5 (#6 was inaccessible due to the downpipe and I gave up). The adjustment method is pretty fiddly and may have been hampered by the lifters not getting enough oil until the car has been running for a bit. I did prime the engine but there’s no way to really know if I was completely correct in this approach. There was only a 10-15% difference between cylinders and this is considered acceptable so I left it at that. I also noticed that I had approximately 10 psi on start more than before. I think this is attributable to the design of the lifters.
I borescoped #4 and saw some scrape marks in there - I hope they're from the borescope and not the valves hitting the pistons.
The truck ran much better and sounded very good indeed. I have always had a ticking noise and I think this is down to a mistake I made when I first assembled it. The noise appears to have gone and I have attributed it to 2 collapsed lifters that I removed. Once I have the exhaust crossover sealed properly, it should be a quiet engine. The exhaust is a different matter entirely but that is a deliberate design.
Lifter problems
I rewired my dash and a few other things to make the underside of the parcel shelf and passenger seat area more clutter free and I am pleased with the results. I have a new PLX gauge on the way (DM 6 multi gauge) and also now have an Exhaust Gas Temperature gauge. It’s basically cosmetic as it isn’t much good as a tuning tool but it fills a hole and should be interesting when the turbo and alky are powered up! I need to get a bung welded in to the down pipe and it is SS so is another little job for me. I might be able to get away with a drill/tap but I’m not sure about tapping stainless steel (RPM downpipe).