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RedSquirrel

Member Since 16 Sep 2012
Offline Last Active Dec 08 2022 12:55 PM
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Topics I've Started

Ignitor “Thermal Compound” Reason For No Start?

08 December 2017 - 05:41 PM

Hey all. So I thought I would pass along some advice that may help others with a Ist Gen that won't start.  I am wondering if it might have something to do with a weird interaction with the rain/humidity and the "thermal compound" on your ignitor (a.k.a. "ignition control module").

 

This seems to have been the case for me.  On two different occasions about a year apart I've had the following occur.  I was working on adjusting the valves and I had the distributor cap removed (so that I could watch the rotor turn to different positions while rotating the crankshaft with my ratchet). At some point during the job, it started to rain. I did not have time to put the cap back on the dizzy or put the valve cover back on the engine. Instead, I just closed the hood and let the car sit for a few days until it was the weekend and the rain had stopped and I was ready to finish the job. Once I did finish adjusting the valves, I reassembled everything and tried to start car, and to my surprise it wouldn't start!!   I could hear the fuel pump "buzz" when I turned the key so I did not think I had a fuel issue.  And when I used my spark plug tester I found that all four plugs had spark.  So now I'm really annoyed, and bummed out, thinking I did something wrong to the valves, or that my timing belt slipped a tooth, or who knows what.  But in the back of my mind, I kept remembering that it had rained and I wondered if moisture had somehow caused some mischief in the dizzy. But I was not excited about opening it up to see what was going on...so I took the easier route and said "hmmm....maybe the rain messed up the ignitor. That should not be difficult to swap out". (on the 1987 it is easy to get to. It is bolted to the underside of the dizzy). So I removed it and noticed something.  The thermal compound had slid up against the 4 metal pins. (a little background: I guess the ignitor is sort of like a cpu in a computer and it gets hot. Just like in a computer, there is usually some "heatsink compound"  applied to the top of the cpu, sandwiched between it and the fan. It helps the heat flow up into the fan where it gets exhausted, thus better cooling the chip. It sound like there is some mystery around what this stuff is in a car, as shown by this discussion here.  In my case, since I occasionally tinker with computers, I already had some of this heatsink compound, and I just used that.)

 

All I know is this: I wiped most of the stuff off, especially so that it was not on the pins. Then I reassembled ignitor and tried starting the car. Bingo!  It started right up!  So I'm not sure what all this means, but may be someone else has a theory. Maybe something is shorting out and it is not flowing through the pins like it needs to.  Maybe the amount of thermal compound I had was not a problem as long as everything is sealed and moisture is not getting in...but once it gets in, it condenses on top of the compound (?) and perhaps makes more of it slide down onto the pins and shorts something out? Maybe I still have enough spark to light my spark plug tester, but not enough for the voltage to jump the air gap at the end of the spark plug and actually ignite the air/fuel mixture.  I really don't know. And I may be totally mis-remembering the situation, but I think cleaning off most of the compound was all I did to get car to run again. Anyway, I hope this helps someone else.


Using Rope Instead Of Removing Cylinder Head

08 October 2017 - 09:17 PM

hey all, so I have been thinking for a long time that I probably need to replace the my valve stem seals.  I've owned my 87 Crx Si for over 10 years and never replaced them and I doubt the orginal owner did.  I have been having the symptom of fouled spark plugs (especially #2 and#3 plugs ) where they are black with oil/carbon and what looks like dusty granular particles (looks like dirty sand particles). I've read that this probably means oil is leaking past the seals because they crack in their old age.   
 
But I really don't want to remove the cylinder head. I'm a novice mechanic and don't really want the hassle.   While browsing youtube, I ran across a few people who claim success with using a rope trick in lieu of removing the head. Here are 2 examples:  here and here.   If you don't want to watch the video, I'll give you the quick summary.  (Admittedly, I'm a novice mechanic so please correct me if I get this wrong). I guess when you replace your valve stem seals, you will be disassembling the valve springs, stems, seals in such a way that the stems could actually fall down into the lower part of the engine, which is a total disaster. At that point, you have no choice but remove the head so that you can retrieve them, which is the big time-waster we are trying to avoid. Thus, most people who attempt this job hook up compressed air to some sort of modified sparkplug-type attachment, which allows air to pass through  the attachement  and  pressurize the combustion chamber which keeps the valves pushed up, so they defy gravity and do not fall once you disassemble everything. You then replace the seals and then reassemble everything and you are done, and pat yourself on the back for not having mess with removing the head.  So it sounds like that's how most mechanics do it. But if you like the average Joe like myself who does not have access to a compressor, you search for alternatives.  Apparently, some clever folks on youtube claim that you can do the job with a rope instead of a compressor. I guess you insert rope into the combustion chamber, then slightly rotate the engine with our ratchet  toward TDC so that the rope presses up on the "cieling" of the chamber, thereby keeping the valves elevated while you replace valves.   So having said all that, now I can finally ask my questions:  has anyone done this on an 87 CRX??  What was your experince?  Did it work? Any hidden dangers?  My first concern is that my spark plugs are "horizontal" instead of vertical, and the radiator is blocking some of my access. If I had vertical plugs, I've got gravity helping put the rope into the chamber. But since my plugs are horizontal, it might be tougher to insert them into the chamber since gravity is less helpful.  What do you all think? 
 

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