Fixing over compression on a 2FE (Camshaft analysis?)
- Thread starter ChaserFJ60
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JDNs78FJ40
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I don't have a timing light so can I just rotate ever so slightly, tighten, test drive and repeat until cured? Or is this something that requires a good timing light?
If you planed the head and decked the block and the pistons were lifting the head it sounds like you may have a lot higher compression than you may think you have. I’d be wondering how close your valves are to the tips of the pistons during operation. How thick was your head gasket?
I've had my share.. bushings instead of bearings and improper lube for one.
Hahahaha! There are many ways, but an advance-able light from O'Reilly's is about $120. It's by far the easiest away. The whiskey glass technique is way cool, but better check your homework with a timing light. It's not like there are $2000 motors laying around in every junkyard. But yes you will do it that way with a light or not.
Amazon product ASIN B000EVU8J8
- Thread starter
- #28
No idea, they seemed pretty reputable based off of online reviews.
Im not trying to get crazy i just want to drive to school
Does your exhaust pop too?
So I ended up reseting the EFI computer because why not, After some hard stumbling she came back to life. I have the timing set back quite a bit now and the clacking has seemed to vanish, and the exhaust pops on deceleration have returned. I have 10,500miles on the rebuild with new pistons so hopfully any catastrohic failure would have occurred by now. I guess i'll try a true higher octane fuel next time around and see how far I can set the timing without that dreaded clacking.
I wouldn't worry about exhaust popping to much on a deceleration or down hill on a modified old engine like these.
You could install an Air/fuel ratio gauge and a vacuum gauge to help you fine tune it over time. Tracking your gas mileage is a good idea.
You could install an Air/fuel ratio gauge and a vacuum gauge to help you fine tune it over time. Tracking your gas mileage is a good idea.
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- #30
I already have a vacuum gauge, it sits at 15hg at idle.
I might get an air/fuel gauge for giggles and
You might check the paperwork or get in touch with them about the compression ratio. People have had too much shaved off and we're SOL. Based on what you have said, I don't believe this is your problem except to part about the head not fitting without the head gasket.No idea, they seemed pretty reputable based off of online reviews.
Im not trying to get crazy i just want to drive to school
Does your exhaust pop too?
So I ended up reseting the EFI computer because why not, After some hard stumbling she came back to life. I have the timing set back quite a bit now and the clacking has seemed to vanish, and the exhaust pops on deceleration have returned. I have 10,500miles on the rebuild with new pistons so hopfully any catastrohic failure would have occurred by now. I guess i'll try a true higher octane fuel next time around and see how far I can set the timing without that dreaded clacking.
- Thread starter
- #32
I doubt contacting them would go anywhere, They didn't install a welch plug properly so it fell out and dumped oil. It was way quicker and cheaper to fix myself so thats what I did. and Its been well over a year so any "warranty" is gone. I didnt specify alot of things and the valves were cut wrong, etc. But its ran fine for 10k miles.
Im at a point in time where I cannot afford to undergo any catastrophic failures. This is my daily car and it has to take me to school every day now. There is no backup car and there is no backup funding. University has drained me dry.
Who else remembers FJ40Jim talking about the later big cap distributor centrifugal advance over-advancing problem? It was caused by the rubber covered pins that limited the advance weight travel. The rubber crumbled off over time allowing additional advance, making total advance ( centrifugal + vacuum) excessive.
- Thread starter
- #36
The had a basic frind, i think a chevy spec? nothing bad just not perfect
- Thread starter
- #37
is there a thread you can link to? My timing doesnt chatter untill ive been driving for 10+ min. Sometimes It wont start clacking until and hour after driving
The stop pin bushing can be replaced with a nylon or aluminum equivalent - 1/4" OD X 1/4" length sized for a #8 screw.
- Thread starter
- #39
Is this for the FJ60 dizzy exclusively? I have an Fj62 dizzy. Im gonna pull the cap tomorrow to look anyways. Yaknow a library of pictures of every single engine part would be really helpful. I think if I ever rebuild my engine again Im gonna try and photo document every engine component and put it into one library.
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Well it's been hot outside. High ambient temps give higher intake air temps which makes a motor more prone to Ping. Since you have higher compression than stock, I would recommend a higher octane during warm times of year. Iron cylinder heads are more prone to have hot spots in the combustion chamber so they are more sensitive to higher compression ratios. A snorkel would give you cooler intake air temps if you want to try that. You can also try setting the base timing a few degrees more retard in the summer. If it's pinging while towing then you should run higher octane when towing. Towing also induces pinging more. Pinging causes a loss on power and its hard on the head and pistons. So it needs to be addressed.