Timing problem
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
Timing problem
Hey guys! Here is the issue... I adjusted my timing according to the Lars timing docs and was having a detination problem. I emailed Lars and he told me to do a TDC test and here is the results. What do I do from here? It would apper that the balancer has slipped.
Any suggestions or input is greatly appreciated.
Any suggestions or input is greatly appreciated.
Melting Slicks
Joined: Mar 2005
Posts: 2,095
Likes: 299
From: Midlothian VA
Yup, in the short run that's your simplest solution.
In the long run you need to replace the balancer.
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
Here is how I arrived at it.... I am working alone for the most part. I hook a compression test guage up to #1 and hand cranked until the needle moved up. I then put a long piece of wire in the plug hole and hand cranked until I had the piston at it's highest point, moving back and forth to verify.
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
but it just has to stay put long enough to time the motor.How about remark the balancer and see how it runs. See if you can get it set to 12-16* or whatever you need to get you to 36* or so. Drive it around for a bit and note the difference in performance. Then you can decide if you want to tackle that project.
PS. you know, once you have the balancer off, the cam is just behind that timing cover. I'm just sayin...
Last edited by johnt365; Nov 16, 2012 at 09:10 PM.
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Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
but it just has to stay put long enough to time the motor.How about remark the balancer and see how it runs. See if you can get it set to 12-16* or whatever you need to get you to 36* or so. Drive it around for a bit and note the difference in performance. Then you can decide if you want to tackle that project.
PS. you know, once you have the balancer off, the cam is just behind that timing cover. I'm just sayin...
Drifting
Joined: Dec 2004
Posts: 1,714
Likes: 42
From: Austin Texas
Its not that easy. It looks like you are 10* off. You need to know two pieces of information.
1. How much advance do your mechanical advance weights pull in?
2. At what rpm is the mechanical advance "all in".
If you were all in at 2600 then you would be at about 24* and if your mechanical pulls 20* then you are at base time of 4*. Lots of Ifs there.
Do the balancer when you do your cam. For now, I would remark the balancer and see what you get. Do you have HEI? Lars recommends a kit by Mr. Gasket 928g. Start with the lightest springs. Then, wrap a rubber band around the weights so that they do not open and set your base timing. You really need a dial timing light. Remove the rubber band. Lets say you set the timing at 12* base. Then free the weights and rev the motor and see what the highest reading is and note the rpm. If it reads 32* then you know you have a 20* mechanical advance. I'm just throwing numbers out but you get the picture.
1. How much advance do your mechanical advance weights pull in?
2. At what rpm is the mechanical advance "all in".
If you were all in at 2600 then you would be at about 24* and if your mechanical pulls 20* then you are at base time of 4*. Lots of Ifs there.
Do the balancer when you do your cam. For now, I would remark the balancer and see what you get. Do you have HEI? Lars recommends a kit by Mr. Gasket 928g. Start with the lightest springs. Then, wrap a rubber band around the weights so that they do not open and set your base timing. You really need a dial timing light. Remove the rubber band. Lets say you set the timing at 12* base. Then free the weights and rev the motor and see what the highest reading is and note the rpm. If it reads 32* then you know you have a 20* mechanical advance. I'm just throwing numbers out but you get the picture.
Last edited by johnt365; Nov 16, 2012 at 09:30 PM.
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,853
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
How hard it is.. it's really not all things considered.
There is really no way to determine your timing with a balancer that is moving. If you make a new reference line on the balancer who is to say it won't move when you start the engine the next time.
If you are trying to just get the car running I suggest you set it at high vacuum for now.. until you can get that balancer off the car.
IMHO,
Willcox
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
Well, I still have a rattle in the engine under a load. I will continue to retard it until it stops. Man! I have so many issues with this thing. Falls on its face at cruising speeds. Vibrations in my console and something in the front right wheel sounds like it is about to come apart under a load. Hahaha boy I sure love her though!
Former Vendor
Joined: Aug 2006
Posts: 76,656
Likes: 1,853
From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
Well, I still have a rattle in the engine under a load. I will continue to retard it until it stops. Man! I have so many issues with this thing. Falls on its face at cruising speeds. Vibrations in my console and something in the front right wheel sounds like it is about to come apart under a load. Hahaha boy I sure love her though!
Thread Starter
Drifting
Joined: Aug 2012
Posts: 1,650
Likes: 2
From: Tulsa Oklahoma
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
You can buy a vacuum gauge from about any car parts store. They are not expensive. You just want to "T" it into the vacuum line coming off the intake manifold. When the car is warmed up and at idle, very slowly move the distributor...either direction...until you locate the point where vacuum level is highest (max vacuum at idle). That's the spot Willcox was referring to.
That will not be the same setting as Lars' paper describes. But, it will allow the engine to be set well enough for you to drive the car and see if you still have detonation (or not) and allow you to run the vehicle to see if the timing reading stays at the same mark from day to day.
You should use the light to read timing when MAX vacuum reading occurs. Then read timing when the dist vacuum can line is removed (and plugged) and also when it is connected. If the readings don't differ, then your advance can on the distributor is bad. [BTW, you did remove that advance can line and plug it when you read the timing at idle, didn't you?]
That will not be the same setting as Lars' paper describes. But, it will allow the engine to be set well enough for you to drive the car and see if you still have detonation (or not) and allow you to run the vehicle to see if the timing reading stays at the same mark from day to day.
You should use the light to read timing when MAX vacuum reading occurs. Then read timing when the dist vacuum can line is removed (and plugged) and also when it is connected. If the readings don't differ, then your advance can on the distributor is bad. [BTW, you did remove that advance can line and plug it when you read the timing at idle, didn't you?]
Last edited by 7T1vette; Nov 17, 2012 at 01:44 AM.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
Your balancer has slipped, as we predicted in our e-mails. The next thing the balancer will do is come apart. I've seen it happen several times, and when it comes apart, it will rip off your fan shroud, cut the water pump right off the front of your block, put holes through your hood, and, if you're timing the engine when it happens, it will take your head off.
Replace it.
Then, time the engine.
Lars
Replace it.
Then, time the engine.
Lars
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
Your balancer has slipped, as we predicted in our e-mails. The next thing the balancer will do is come apart. I've seen it happen several times, and when it comes apart, it will rip off your fan shroud, cut the water pump right off the front of your block, put holes through your hood, and, if you're timing the engine when it happens, it will take your head off.
Replace it.
Then, time the engine.
Lars
Replace it.
Then, time the engine.
Lars
Replace it. But if you're not going to replace it its easy to figure out the timing. You're at 44 degrees (34+10) which explains the detonation. You could set the timing at 24 deg and be OK, at least until the balancer grenades.