Trying to time my engine

[Lawrence M.]

Re: Trying to time my engine

DSCN5456.jpg

Michael

Your #1 wire should be to the right side of the points adjustment window and the distributor clocked as shown. This Distributor is at 8 BTDC instead of the factory 4 BTDC.

[Mark E.]

Re: Trying to time my engine

Michael,

To answer your question about the timing tab: Yes, "A" means After Top Dead Center, and "B" means Before Top Dead Center. Some timing tabs, like the one shown below, actually say AFTER and BEFORE.

Looking at the harmonic balancer and timing tab from the left (driver's) side, the engine rotates in the downward direction so that's why the BEFORE marks are ABOVE TDC (zero) and the AFTER marks are BELOW TDC (zero).

As mentioned before, since it ran fine on the dyno, the most likely culprits are either the timing light hooked to the wrong cable, or the dial-back light isn't adjusted properly. The good news is this isn't a serious or expensive problem. It will turn out to be something simple and give you a DUH moment when found.


timing tab.jpg

[Michael L.]

[Perry M.]

[Michael L.]

Re: Trying to time my engine

Guys,

As you can see in the pic below, my timing mark has the A above the zero, which I took to mean After TDC. This completely screwed me up. After taking the pic and blowing it up to look at it, it's clear to me now that the lower letter is an R, for retard, not a B for before. So Perry is correct. A is for advance. Guess that is item number 12 I can cross off my list of the 15 things that are out of wack. Only 14 more to go! LOL

Mike


vette timing tab.jpg

[Mark E.]

Re: Trying to time my engine

Well, we learned something. Some tabs say BEFORE and AFTER, and some say A (for Advanced) and R (for Retarded).

[Frank D.]

Re: Trying to time my engine

Well, we learned something. Some tabs say BEFORE and AFTER, and some say A (for Advanced) and R (for Retarded).

As I stated way back in post #5

[Mark A.]

Re: Trying to time my engine

I'm going to stick my nose in here, and maybe get it bent a little. But I think this needs to be said. I own a restoration shop, and specialize in C-3 corvettes. I'm sorry to hear you had an unsatisfactory dealing with a supposed professional shop. No professional who knows what they are doing, and pays strict attention to detail, will leave off a VIN tag. But please do not make the mistake of thinking all restoration shops overcharge customers and do shoddy work. I have built Top Flight cars, and do everything in my power to make a customer happy. I have had people like you who have come to me with a problem with their car, but they were more interested in expounding on how the last guy ripped them off, and they don't trust anyone. I know right away, they are not going to trust me either, which is a shame because I could solve their problem. So don't put all shops in one basket. There are still good people out there. Good Luck. Mark

[Loren L.]

Re: Trying to time my engine

See Post #4.

[Michael L.]

Re: Trying to time my engine

I hear you Mark. The shop I used does good work. They do not specialize in corvettes they do all types of cars but the do the body and paint for a fairly well known corvette restoration guy in town. While my car was there they had several other corvettes in there. It is a large shop with probably 20-25 cars getting done at a time, which probably contributes to some things getting missed from time to time. The tag being left off is frustrating but its not a capital crime. I contacted them and they were apologetic and stated they will take care of it, of course. I have a good relationship with them and appreciate all the work they did for me, as I do for all the shops that have done work for me. As for the cost, I do not believe that I was ripped off. This hobby ain't cheap, as I've learned from doing many other cars as I stated. I believe the cost is just what it is. The first guy that I gave this car to was a total crook and hack, he's not at all what I'm talking about. What I'm talking about is more the reality of what taking the car, or any car, to a shop would entail. Just the aggravation and hassle of getting the car transported somewhere and likely 3-4 weeks of time to get the car in (most reputable shops have a wait time for work) or they take the car now but they can't get to it right away and either way it takes 3-4 weeks for the car to be sorted out and it will undoubtedly take a couple of days billable labor to sort out and at the shop rate of $85/hr it adds up quick. I've already made significant progress on the car. I've checked the timing and wires, and as I posted earlier it was right on, as the flawless dyno run three years ago would indicate. That took me a couple of hours to do and that, plus changing the condenser, basically solved the spark and timing issues I was having, which has now obviated most of the need to send it to a shop. I believe the main problem all along was the carburetor. I'm going to swap it out with a stand-in for now while I troubleshoot the rest of the car. Part of the problem is my previous projects have all been different brands, Mustangs, AMXs and GTOs. This is my first Chevrolet of any kind. Makes things like the timing tab and other stuff just a little tougher to sort out.

[Michael L.]

Re: Trying to time my engine

Just wanted to update you guys. I decided to swap out the distributor for an MSD unit. I used an MSD coil and also temporarily wired in a 6AL MSD ignition just to optimize the spark of the car to see if I could eliminate ignition as a potential source. The car started immediately and ran flawlessly. I think there were a combination of things that probably contributed to it, but I'm glad to have it running and to be able to work out the kinks and I'll slowly work it back to the factory equipment over the next few months. I'll be sending the carb and distributor out to be looked at while I work on other stuff on the car. Thanks for everyone's assistance with this.

Mike

[Mike E.]

Michael,

To answer your question about the timing tab: Yes, "A" means After Top Dead Center, and "B" means Before Top Dead Center. Some timing tabs, like the one shown below, actually say AFTER and BEFORE.

Looking at the harmonic balancer and timing tab from the left (driver's) side, the engine rotates in the downward direction so that's why the BEFORE marks are ABOVE TDC (zero) and the AFTER marks are BELOW TDC (zero).

As mentioned before, since it ran fine on the dyno, the most likely culprits are either the timing light hooked to the wrong cable, or the dial-back light isn't adjusted properly. The good news is this isn't a serious or expensive problem. It will turn out to be something simple and give you a DUH moment when found.


[ATTACH=CONFIG]99617[/ATTACH]

[Mark E.]

Re: Trying to time my engine

Mike,

I've see quite a few timing tabs with BEFORE and AFTER. One example is Pat Hulst's '72 Bowtie:
https://www.flickr.com/photos/124695...57649252735124

Timing Tab.jpg