Timing oddity
Thread Starter
Racer
Joined: Jan 2020
Posts: 388
Likes: 117
From: Tacoma, Wa
Timing oddity
I’m still trying to tune out part throttle/cruise popping in the exhaust and surging. Ive been messing with the timing without using my light. Today I went to check where I’m at with timing, and the mark was waaaay off. I dont even see the mark until I dial my gun to 80*. At idle, with my gun at 80*, the mark is at the 12 oclock position on the balancer. When I raise dial, the mark moves downward toward the bracket I’m supposed to be lining everything up too. Are these the symptoms of a slipped balancer?
I gotta long trip this weekend where i’ll be in the 3000-3500 range for 3 hours straight. I’d like to get it dialed in beforehand.
I gotta long trip this weekend where i’ll be in the 3000-3500 range for 3 hours straight. I’d like to get it dialed in beforehand.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
My 79 L82 damper broke/slipped within the first few years
Kinda a PITA job to replace. The diameter didn't allow me to get it off because of the cross member frame. I had to pull the two engine mount bolts to jack up the front for removal clearance. Then the timing cover for a new seal
So I bought the SFI Fluid damper 6.125 inches
Kinda a PITA job to replace. The diameter didn't allow me to get it off because of the cross member frame. I had to pull the two engine mount bolts to jack up the front for removal clearance. Then the timing cover for a new seal
So I bought the SFI Fluid damper 6.125 inches
Thread Starter
Racer
Joined: Jan 2020
Posts: 388
Likes: 117
From: Tacoma, Wa
Thread Starter
Racer
Joined: Jan 2020
Posts: 388
Likes: 117
From: Tacoma, Wa
this is what the mark looks like at tdc. Its a lot closer than I thought it would be, but still off. I imagine the new mark with be where that hole and indent is on the bracket. Does this look in line with the symptoms above?
Race Director
Joined: Mar 2017
Posts: 11,929
Likes: 4,497
From: Virginia
You should have opened with this photo, and we wouldn't have wasted time with advice.
You need a new harmonic balancer. Your outer ring has slipped BACKWARDS a half inch. I would not drive that car until it is replaced.
You need a new harmonic balancer. Your outer ring has slipped BACKWARDS a half inch. I would not drive that car until it is replaced.
Thread Starter
Racer
Joined: Jan 2020
Posts: 388
Likes: 117
From: Tacoma, Wa
does driving with a slipped balancer cause damage? I had it tuned in Feb, and nothing was mentioned to me. I didnt even look down there until august i’d say, when issues started to arise. It looked like it does now, so its been in this position for at least a month to 5 months
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Race Director
Joined: Mar 2017
Posts: 11,929
Likes: 4,497
From: Virginia
does driving with a slipped balancer cause damage? I had it tuned in Feb, and nothing was mentioned to me. I didnt even look down there until august i’d say, when issues started to arise. It looked like it does now, so its been in this position for at least a month to 5 months
Like I said, I would not drive it like that. I did not add that I have plenty of other cars to drive while I wait for the part, I have the tools for the job, and easy access to R&R with no shroud or clutch fan in the way.
Thread Starter
Racer
Joined: Jan 2020
Posts: 388
Likes: 117
From: Tacoma, Wa
It is not fully functioning as a harmonic damper. At a minimum, that can put extra stress on your crank and bearings.
Like I said, I would not drive it like that. I did not add that I have plenty of other cars to drive while I wait for the part, I have the tools for the job, and easy access to R&R with no shroud or clutch fan in the way.
Like I said, I would not drive it like that. I did not add that I have plenty of other cars to drive while I wait for the part, I have the tools for the job, and easy access to R&R with no shroud or clutch fan in the way.
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
You should go out and just rev the **** out of it and bang some gears and see if the 6 pound outer ring goes through your hood or goes down and hits the road and bounces up between your legs. 
it's 1979?????
it's 1979?????
Thread Starter
Racer
Joined: Jan 2020
Posts: 388
Likes: 117
From: Tacoma, Wa
I kinda did that 2 days ago
When your friends little brother wants a ride, you gotta make sure he has fun
Tech Contributor
Joined: Aug 1999
Posts: 14,375
Likes: 6,375
From: At my Bar drinking and wrenching in Lafayette Colorado
That's not how you do a TDC verification. You could be off by over 25 degrees doing it like that. Do the job correctly so you know if you have a problem.
Tech Contributor
Joined: Aug 1999
Posts: 14,375
Likes: 6,375
From: At my Bar drinking and wrenching in Lafayette Colorado
For 1/3rd the cost, you can just buy a new one and have it delivered to your doorstep in 2 days.
Last edited by lars; Sep 17, 2021 at 09:00 PM.
Thread Starter
Racer
Joined: Jan 2020
Posts: 388
Likes: 117
From: Tacoma, Wa
I actually just finished ordering the new parts. I’m going to open up the timing cover and see if the original nylon gears are still there. Previous owner did a cam swap in the 90s but didnt remember if they installed new gears.
Thread Starter
Racer
Joined: Jan 2020
Posts: 388
Likes: 117
From: Tacoma, Wa
Balancer was an easy job. Got it dialed in, and still some popping. Looks like I need a vac advance canister with less advance. Thanks everyone 👍🏼
I did end up going on the road trip, I posted about in in C3 General. I detuned the motor a bit so I didnt have the performace I wanted but it ran perfectly.
I did end up going on the road trip, I posted about in in C3 General. I detuned the motor a bit so I didnt have the performace I wanted but it ran perfectly.
Last edited by Cmurray79; Oct 7, 2021 at 05:58 PM.
Racer
Joined: Apr 2019
Posts: 300
Likes: 83
timing
lets say you have every thing togeather right. start the enging let it warm up. hook up timing light, loosed the dist hold down bolt, with timing light move dist counter clock wise and see if timing mark moves up to where it should be 10 to 12 degrees