I have been battling an oil leak that appears to be coming from one of the oil pump bolts. I know you have to add sealant to the threads of the top bolt, but I have never heard about it on this bolt.

I was thinking of pulling it out, covering the bolt the thread sealant and putting it back in there.

Has anyone ever run into this? What was their resolution to the problem?

Thanks


From the bottom



From the top (no oil leak above the bolt)

 

Did you do any work in there before the leak started (timing chain)? I would wonder if maybe the rubber o-ring gasket on the back of the oil pump isn't seated right, letting it leak because I think you are right about not putting sealant on that bolt. I didn't anyways and no leaks.

 

^^ This. I always put a thin coat of sealant around the o-ring to keep it from moving when it goes vertical.

 

Thanks for the input guys.

Full disclosure:

I put in a new engine about 1 year/ 8000 miles ago. Before I installed the engine I vacuum checked it to ensure it wouldn’t leak oil (I always do this).

Fast forward to a month ago, I noticed that it started dripping a bit from the front pass area of the cover. I was pissed, but just kept my eye on the oil level. Two weeks ago it started getting really bad, as in I lost 2 quarts of oil going to work and back the last day.

So that Friday night I pulled it into my shop to tear down. Clearly it was coming from what seemed to be that bolt. I pulled it apart and found that my oil pump had three large cracks in the boss for the oil pressure regulator (very odd failure mode). The oil pump o-ring for the pump appeared to be in fine (I do use a bit of sealant to hold it in place as well). Assuming the oil was coming from the cracks I replaced the oil pump, o-ring (using sealant to hold it in place), front main oil seal, and a speedy sleeve on the harmonic balancer.

It has started leaking from that bolt again, so my cracked oil pump hypothesis was not quite correct. It is possible I screwed up the o-ring this time, but I currently have the same failure mode as before and I know the o-ring was properly placed then.

Other ideas? Things to check/look for when I take it apart?

 

Did the oil pump crack in the same spot? What kind of pump are you using and how much torque are you applying? Check for any gouges on the mating surfaces. Also if you can, check the timing cover for any cracks.

 

So I haven’t gotten the new oil pump off to see if it is cracked, but I would presume it is not.

The first one was the unit that came with the engine (had “ROCK” cast into it), the second one (that is currently on it) I made sure to find an Asin.

On the tq front, I didn’t put a tq wrench on it, but I was careful to be gentle because the tq spec on those bolts is quite low. I tq’ed them in a pattern to make sure it was seated evenly and then just snugged them up. I went back and checked the bolts when it first started leaking to make sure none of them were loose, so they may be over tq’ed a bit.

No obvious gouges on the mating surfaces, but I am going to be looking at everything with a very critical eye this time.

 

Digging this one up..... I searched because I have the same EXACT problem. Did you figure out what's going on?? I made it stop a little while by putting a ton of ultra grey on the bolt and shoving it in leak is back though... and that's just ghetto

So I did about the same thing to try to solve it. After further investigation and some naughty words I think I have figured out the issue. EBay parts... that's it. I bought a timing chain cover from eBay and its like an aluminum piece of Swiss cheese. The "hidden bolt" in the head has obvious porosity visible in the threads. BUT, as far as leaking around the oil pump bolt (the long one) I found more porosity within the t-chain cover. One hole and another big hole. With a mirror and flashlight I found them and with a curved dental pick I verified the holes. I assume since they are around some major looking oil passages that oil is being pushed in there. I will confirm once I get a blow gun with a rubber tip. This aluminum has bubbles in the casting everywhere! dun teached me a lesson on buying cheapo crap parts.

More to come... After I find a blow gun.
dead end post no more weooo

 

That bolt is one of the 2 bolts that goes through the oil pump, and through the timing cover, and then into the cylinder block to fasten the oil pump and timing cover.

If oil is only leaking from that bolt as your picture and original posting state I would suspect an internal timing cover gasket failure.

Cracked and or damaged oil pump is possible but unlikely....

A possible fix without removing timing cover and resealing the front of the engine would be:

-Remove bolt clean and dry bolt and bolt hole.
-Apply RTV sealant to the bolt.
-Install bolt torque to specs and let sealant cure for 24 hours.

This may or may not remedy the leak.

If not.. I suspect timing cover gasket/timing cover failure.

 

 

Thanks, I have explored all options you mentioned. The hole in the timing chain cover that said bolt goes through has some porosity or bubbles in the casting. I'm assuming the holes go far enough to let oil in around the bolt between the threads and the head of the bolt. Do you see what I'm saying?

 

I have replace the gaskets twice, sealed the bold with sealer, explored about every option. I'm thinking this is the problem and that a quality timing chain cover will solve the problem. I would like to know if 352ford found the problem and if not maybe its the same deal.

 

The best pic I could get while holding a flashlight mirror and camera... Looks like a chunk missing inside the hole there is another hole further back