Engine/Transmission (1994 - 1998) Cracked Timing Case!

[JHastings]

Think I found my little oil leak problem. Pretty sure it is a cracked timing cover. Pretty sure the KDP got tabbed at least the PO said so.

The crack is below and to the left of the vacuum pump. You can see the thin white line. Seems like a weird place to me. Also not a huge crack, but seems to be leaking oil there or right above the crack. Anyhow, it has to come off and be replaced I think.

Any good sources on these things?


https://www.turbodieselregister.com/forums/attachment.php?attachmentid=70302&stc=1&d=1221616576

https://www.turbodieselregister.com/forums/attachment.php?attachmentid=70301&stc=1&d=1221616576

 

[Vaughn MacKenzie]

Almost looks like a casting seam to me, but kinda hard to tell for sure with less than perfect photography

 

[bnelson]

Before you go to the expense of replacing the timing cover, clean the area with a good brake cleaner / electrical parts degreaser, then apply a thin layer of black hi-temp RTV silicone. Let this set for at least half an hour. Make sure it appears to be sticking to the metal and that there is not an oil "bubble" under it. Then apply two or three more layers of the same silicone a half hour to an hour apart. After the last coat, let it cure overnight before you drive it. If you cannot stop the leak (render the area totally oil-free) before applying the silicone you may want to remove the timing cover and apply ONLY ONE VERY LIGHT COAT on the crack on the inside of the timing cover, followed by multiple coats on the outside. Remember, all the timing cover does is keep the oil in the engine and the dirt out. This repair done properly will last longer than you or your truck will.

 

[GAmes]

Take a look above the vac pump between the IP and the block. That is where my gear case leaked and it dripped at the spot you are showing. It just ran down that valley where the case is bolted to the block. I had mine replaced which requires the cam being pulled, so I took the opportunity to get a PDR cam. If it starts leaking there again I won't spend that kind of money. I will remove the vac pump in order to get access to the valley, clean it with brake cleaner, then coat it with a large bead of black RTV. BTW, if your leak does happen to be the same, check to see if the support brace bolt near the rear of the IP has fallen out. The brace is the same one that the L shaped bracket for the vac pump is bolted to. Above it is the bolt I'm referring to. Hard to see. My theory is that after bolt fell out all the weight of the IP was hanging from the fwd mounting bolts and the result was the case bending away from the block.

 

[JHastings]

You know, it might be a casting seam and actually the oil was coming from above the crack/seam. However, it might be the gasket between block and case. I will look closely tomorrow at the spot again. I cleaned it very well today and this was the only way in which I was able to find the spot.

Can anybody else look at this spot on their case to see if it is in fact a casting seam? Might be the same on your pickup.


Jamie

 

[EDavis]

I think thats a casting seam. I have one on both sides of my timing case. Check your other side about the same spot. I think your leak is coming from somewhere else.

 

[JGK]

Go with what GAmes said. I had the same thing happen though the leak on mine was a little lower - below the vacuum pump. I did just what he did, replaced the gasket and used the opportunity to put in a PDR cam. That was years ago. But the leak is, unfortunately, somewhat common on 12-valves.



Another product you might consider that I like better than RTV silicone goes by the name Right Stuff and can be found at Autozone in pressurized cans and in tubes for use in caulking guns. I think it is urethane based, dries just a bit firmer than RTV, and works extremely well.



-Jay

 

[Dieselnut59]

I cleaned up the cover as mentioned above and used JB Weld on it, with silicone between the cover and block. Never has leaked another drop. This was on my '98 work truck. The cover broke when the dowel pin came loose and went around the cam gear. Remove the front metal cover, clean up and "seal" the housing and be sure to check the tightness of the housing mounting bolts. I removed my bolts, cleaned them and applied blue Lock Tite.

Another thing to check is the seal between the vacuum pump and power steering pump. That has recently began leaking on my '96 and it runs down the side of the block, around the front housing.

I believe there is a seal available from someone on the TDR or Genos...

 

[McCRam]

That seam got me all worked up once as well. I couldn't believe my bad luck. Blown headgasket and a cracked timing cover at the same time. After drinking a few beers I crawled back under and could see things more clearly. :-laf My leak ended up being caused by a loose vacuum pump.

 

[Bob V]

Try tighting all the cover bolts first. Also look closly at the vaccume pump to housing gasket, I had a leak there on my '97.

 

[JHastings]

I checked the timing cover bolts and the leak is definitely not coming from the vacuum pump. I put white paper towel up on there and ran it for a while. I could see the oil, but no oil on the towel.

I bought the "Right Stuff", cleaned it up real good and put a couple of coats on there. We'll see what happens today.


Jamie

 

[Breed]

Could be the seal between the Vacuum Pump and Power steering pump, quite common, happened on my 98, I got the kit from Pete Gould at www.fixinrams.com, worked great and saved $600. 00. pretty easy fix and converts to the new seal which is bulletproof, easy job with the kit, even includes the tools for $59. 00.

 

[JHastings]

It is definitely not that seal. I patched up around the timing case and I think I have it slowed down, but not stopped. I will work on it some more.