2008 M1078 A1R Maryland to California or Bust!

[Bryan 45]

Made it home earlier this evening, Total miles for the trip was around 3200 with zero mechanical issues. No to start working on the little niggles to get them sorted out.

That certainly has to make you feel good about buying the right truck. Congratulations on the easy journey.

 

[GCecchetto]

Okay, R.E. the leaking bolt issue, seems this product might be the thing to use since it's designed to seal threads. Thoughts?

 

[GeneralDisorder]

Okay, R.E. the leaking bolt issue, seems this product might be the thing to use since it's designed to seal threads. Thoughts?

I prefer this:

LOCTITE® 545

Designed for locking and sealing metal pipes and fittings, it’s specially formulated to offer high lubricity for easy assembly and removal.

www.henkel-adhesives.com

But also - pics of which bolt and how do you know it's the *threads* that are the problem? Is oil working it's way up through the threads or coming from under the head of the bolt? These are very different scenarios.

 

[GCecchetto]

Okay, spent more time than I care to admit trying to sort out this oil leak this evening. For context, this leak started after the bracket for the AC compressor was installed. This is the same bracket Acela uses, they buy them from the guy I bought the truck from. When I pulled the bolt that was supposed to be the issue, it was literally dry, full of RTV, but dry. So I thought pulling the bolt was a waste of time, it's completely dry, can't be the problem. I did notice when I pulled the bolt, it wasn't very tight though. Spent a bunch of time snooping around trying to find another spot that might be leaking from. No love, so I cleaned the RTV off of the bolt, to reinstall it. While all the searching was going on some oil appeared, see photo below, at the original bolt location. The oil isn't coming out of the hole though. it's coming out between the plate on the front of the motor and the AC compressor bracket.

So, I reinstalled the bolt dry and checked the other bolts in the bracket, which also weren't very tight, and before anyone asks, no, I didn't spend the time to figure out what the proper torque is, I just felt the bolts weren't very tight for their size going into a cast iron block, so I tightened them so they were tight, but not ridiculously tight. I will take the time to figure out the actual spec, but was just trying to sort the issue out today with limited brain capacity since the divorce I thought I had settled has come back again as a complete......f. ...g nightmare. Was hoping the bolts just weren't tight enough, but after running the motor for 30 minutes, oil started to appear again. I do think it's probably slower than before, but still a leak. So, I think I need to pull the AC compressor and bracket, and put some RTV around the bolt holes between the AC compressor bracket and the plate on the front of the motor, and then clean the hole with brake clean, and then goop up the bolt again and reinstall it.

I'm also thinking the thread sealant I previously posted isn't the way to go because there is now silicon RTV in the hole and pretty much nothing but silicon sticks to silicon, so, I probably need to goop up the bolt with some high temp Permatex and hope for the best.

 

[GeneralDisorder]

That appears to be coming from the timing cover under the bracket. No amount of sealant of any kind on the bolt is going to solve that. The oil isn't coming through the threads - it's coming from between the cover and timing case and you can tighten it till you strip it or break it and oil will still find a way through the imperfectly machined surfaces that lack gasket/sealant between them.

For "thread" sealant to work, there must be something you are trying to prevent coming THROUGH the thread - pipe threads are a common situation, or small block Chevy head bolts that thread right into the cooling jacket.... In this case the oil is leaking from something that's being clamped together by the bolt, not from the bolt threads or from under the bolt head.

You need to take all that apart and clean it and replace the gasket. Item #8 in this diagram:

You can see that the gasket wraps entirely around that hole so unless it has failed there's no way for oil to get into the hole and leak between the cover and the compressor bracket. My bracket is the same and in the same location and is completely dry around and under that bolt since I installed it in April of 2022.

Indeed you should be able to completely remove that bolt and have nothing happen at all if all the other bolts in that cover are tight and the gasket is in place. That's how I installed my bracket - remove bolt, install bracket, reinstall bolt - no oil was ever present.

The other possibility is that it was over-tightened or bottomed out and the threaded boss in the timing case is cracked or damaged allowing oil into the hole.



You will also need #19:



And possibly other gaskets and seals.

 

[GCecchetto]

That appears to be coming from the timing cover under the bracket. No amount of sealant of any kind on the bolt is going to solve that. The oil isn't coming through the threads - it's coming from between the cover and timing case and you can tighten it till you strip it or break it and oil will still find a way through the imperfectly machined surfaces that lack gasket/sealant between them.

For "thread" sealant to work, there must be something you are trying to prevent coming THROUGH the thread - pipe threads are a common situation, or small block Chevy head bolts that thread right into the cooling jacket.... In this case the oil is leaking from something that's being clamped together by the bolt, not from the bolt threads or from under the bolt head.

You need to take all that apart and clean it and replace the gasket. Item #8 in this diagram:

You can see that the gasket wraps entirely around that hole so unless it has failed there's no way for oil to get into the hole and leak between the cover and the compressor bracket. My bracket is the same and in the same location and is completely dry around and under that bolt since I installed it in April of 2022.

Indeed you should be able to completely remove that bolt and have nothing happen at all if all the other bolts in that cover are tight and the gasket is in place. That's how I installed my bracket - remove bolt, install bracket, reinstall bolt - no oil was ever present.

The other possibility is that it was over-tightened or bottomed out and the threaded boss in the timing case is cracked or damaged allowing oil into the hole.

View attachment 908427

You will also need #19:

View attachment 908428

And possibly other gaskets and seals.

Yes, it looks like that in the photo, but after cleaning it up and reinstalling the bolt and running it for 30 minutes, you could clearly see that it’s leaking between the bracket and the timing cover, not between the timing cover and the timing case, and I hope it stays that way because removing the timing cover and replacing that gasket isn’t a small job.

 

[GeneralDisorder]

Yes, it looks like that in the photo, but after cleaning it up and reinstalling the bolt and running it for 30 minutes, you could clearly see that it’s leaking between the bracket and the timing cover, not between the timing cover and the timing case, and I hope it stays that way because removing the timing cover and replacing that gasket isn’t a small job.

I don't think you understand. The only way oil can get into the hole to leak from between the cover and the bracket is for the cover gasket to have failed or for oil to be present in the (blind) threaded hole. Neither of these is likely to be fixed by "goop" on the threads. You can keep trying the thing that didn't work the last several times but I think the chances of success are low.

The gasket around the bottom circumference of the hole may be intact. Oil enters the hole around the top circumference (12 o-clock-ish), and leaks out between the cover and gasket because gravity and the gasket being intact around the bottom of the hole. You might get away with sealant on the bracket and the bolt and a copper washer. Have to use a thread locking sealant because lock washers will provide a leak path.....

The right fix is to reseal the cover. Sure it's work but you better get used to that with these trucks. Be glad you don't have to pull the engine.

 

[GCecchetto]

GD, I understand, believe me, I'm just hoping to get this under control for now so I can address some other things that need to be done before continuing to drive the truck. I'm trying get the final stages of divorce done, and will be moving into a new home shortly and would like to have the truck drivable to move my tools to the new House. I understand that at some point I'll likely have to pull the timing cover and address this issue correctly, but for now if I can stop the leak, or even get it to the point of just weeping a little oil that isn't get blown all over the undercarriage of the truck, that will work.

 

[GeneralDisorder]

That is also one of the bolts that holds the air compressor and power steering pump - which is the most common source of cracked timing cases when the bracket bolts that hold the hydraulic (power steering) pump get loose and allow the compressor and the pump to hang unsupported from the timing case. Just FYI. Inspect carefully.

 

[GCecchetto]

That is also one of the bolts that holds the air compressor and power steering pump - which is the most common source of cracked timing cases when the bracket bolts that hold the hydraulic (power steering) pump get loose and allow the compressor and the pump to hang unsupported from the timing case. Just FYI. Inspect carefully.

I didn't see any sign of a crack, but will further inspect the area, and will check the bolts at the hydraulic pump and air compressor to make sure they are tight. Thanks for the heads up.

 

[GCecchetto]

That is also one of the bolts that holds the air compressor and power steering pump - which is the most common source of cracked timing cases when the bracket bolts that hold the hydraulic (power steering) pump get loose and allow the compressor and the pump to hang unsupported from the timing case. Just FYI. Inspect carefully.

Do you by chance have the serpentine belt part # handy for the A1R with the higher amperage alternator? The seller bought a belt based on the parts manual and it was too short, he suspects the higher amp alternator is the cause. Looks like the belt # is no longer visible on my belt. As long as I'm removing the AC compressor I would like to replace the serpentine belt. Thanks

 

[GCecchetto]

You can ignore that last post, found the belt part#.

 

[GeneralDisorder]

The AC compressor runs on it's own V belt and there's two different lengths of AC compressor belts used depending on the type of tensioner....

FMTV: Old A/C Tensioner System Not in TM

Operators, the story on Pages 16-17 of PS 798 (May 19) provided info for A/C belts due to confusion with the addition of a new A/C tensioner system. The old system was left out of TM and here's the

www.psmagazine.army.mil

 

[Mullaney]

The AC compressor runs on it's own V belt and there's two different lengths of AC compressor belts used depending on the type of tensioner....

FMTV: Old A/C Tensioner System Not in TM

Operators, the story on Pages 16-17 of PS 798 (May 19) provided info for A/C belts due to confusion with the addition of a new A/C tensioner system. The old system was left out of TM and here's the

www.psmagazine.army.mil

.
I snagged the link because it has part numbers.
Trying to keep them from disappearing later...



Thanks for finding it @GeneralDisorder !

 

[GCecchetto]

The AC compressor runs on it's own V belt and there's two different lengths of AC compressor belts used depending on the type of tensioner....

FMTV: Old A/C Tensioner System Not in TM

Operators, the story on Pages 16-17 of PS 798 (May 19) provided info for A/C belts due to confusion with the addition of a new A/C tensioner system. The old system was left out of TM and here's the

www.psmagazine.army.mil

I know the AC compressor has it’s own V belt, that’s new on my truck. I was asking about the serpentine belt. Already picked up a new one.

 

[GCecchetto]

.
I snagged the link because it has part numbers.
Trying to keep them from disappearing later...

View attachment 908465

Thanks for finding it @GeneralDisorder !

FYI, a C7 with 260 amp alternator uses Gates K080806 for the serpentine belt. It wasn’t in the part # thread.