Timing marks

[BKahler]

I'm getting setup to change the glow plugs on the truck and I'm going to try the method where you change the glow plug when its respective piston is at TDC.

Ok, so the dumb question of the night , where are the timing marks on the 7.3 IDI ?

I cruised through the factory service manual and also the factory diagnostics manual and didn't see any reference to the pointer that has to be somewhere on the front of the block.

How about it, any hints....

Thanks,

Brad

 

[zigg]

No takers eh?

The timing marks can be covered in oil and hard to see. On the front of the engine(actually on the front plate, not the block) down under the alternator and beside the crankshaft harmonic balancer will be a plate sticking out with a couple tube looking things on it. That's where the various adapters can be mounted to set timing. There is also on that plate(you might have to use some wd40 to clean it off) some marks which indicate the "0" mark for TDC, and you should see a scribed line, and a "0".
Now look at the surface of the harmonic balancer where it passes close to that plate, and somewhere on that surface will be a corresponding line etched into the balancer. You may have to rotate the engine to find it and clean the surface off too. When the line on the balancer is exactly in line with the line on the plate, then #1 piston is at TDC. There's a bit more to it than that, but essentially that's it.

I have written a small article about this. Hopefully it'll help you with it...click here to see it..

Zigg

 

[BKahler]

No takers eh?

The timing marks can be covered in oil and hard to see. On the front of the engine(actually on the front plate, not the block) down under the alternator and beside the crankshaft harmonic balancer will be a plate sticking out with a couple tube looking things on it. That's where the various adapters can be mounted to set timing. There is also on that plate(you might have to use some wd40 to clean it off) some marks which indicate the "0" mark for TDC, and you should see a scribed line, and a "0".
Now look at the surface of the harmonic balancer where it passes close to that plate, and somewhere on that surface will be a corresponding line etched into the balancer. You may have to rotate the engine to find it and clean the surface off too. When the line on the balancer is exactly in line with the line on the plate, then #1 piston is at TDC. There's a bit more to it than that, but essentially that's it.

I have written a small article about this. Hopefully it'll help you with it...click here to see it..

Zigg

Hi Zigg,

Actually your article is the one I was refering to in my original post.

I have NO desire to pull the heads on this truck and will use any trick I can to keep from doing so.

Thanks for the info.

You must be registered for see images

I'm hoping to have time to try and change the GPs later this week. I'll let you know how it works out.

Thanks,

Brad

 

[BKahler]

No takers eh?

I have written a small article about this. Hopefully it'll help you with it...click here to see it..

Zigg

Hi Zigg,

Well I got the job of replacing the glow plugs done. The good news is I followed your instructions exactly and managed to get all of the plugs changes without a problem. The bad news is I made one mistake, identifying which was #1 cylinder. I've always known that right and left is referenced to the driver facing forward but for some reason while standing in front of the truck I told myself, "ok, right hand side is #1" so what did I do? I used my right hand while facing rearward

I didn't realize my error until I was fiddling with what I thought was #3 glowplug. I was sitting there wrenching away and noticed the numbers on the intake manifold.

Fortunately none of the plugs had swelled and all of them came out without the slightest bit of problem.

The truck had two AC GPs, one Autolite GP and the rest were Beru GPs. One of the AC plugs was dead, one of the Beru's had a high resistance reading and the other AC GP had a high reading. The GP controller now cycles the WTS light for 10 to 12 seconds the first time around which I believe is about right for operation.

Starting is better but on a 50 degree day I had to cycle the GPs a second time before it would fire. I'm guessing I still have something wrong somewhere but not really sure where to start. What other issues can I look for that might cause difficult starting?

On our trip of about 1700 miles round trip I would guess I used on average about 1 quart in each 350 miles or so. Might be a little better than that, just can't remember for sure.

Any thoughts?

Thanks,

Brad