pushrod tube leaking?

What causes a pushrod tube to look like is crooked or not in line? when I got it back from the mechanic it looked misalighned but did not leak now it leaks, less than 300 miles put on engine, should this be warranty work? Cabanaboy

The head compesses the tube (on a T1 but not T4) so head has to be loose - like from a pulled stud. What work did your mechanic just do? Retorquing the heads - per chance? Warranty - if pulled stud probably would be - usually when rebuilding old block steel case saving studs are machined into block to prevent this. Would think new high end blocks would have that done already.

thing that make you go hmmmmmmmm.

hmmmmm.....Wolfgang seems to be on a loose stud/loose head kick this week, and while that is certainly something to consider, I would be more inclined to think that the mechanic inadvertently pushed something against the pushrod tube, thereby bending it just enough to make it begin to leak (it doesn't take much). Lots of things often do this, like floor jacks in the wrong hands (those yielding said floor jack will always be the first to say; "But I never touched that!!")

After all.....if the head was loose, chances are more likely that more than one tube would be leaking, and if the head is THAT loose you'll hear some strange rattling going on, especially at idle, caused by blow-by at the head/barrel seal (where there is no seal).

Pushrod tubes leak at two different places: (1.) at the sealing O-ring at each end and (2.) from a crack in the bellows (caused either from fatigue over time (hot/cold flexing) or distorting the bellows by pushing the tube to one side. I've seen a lot more bellows leaks than end seal leaks, especially if the tube is assembled with RTV.

THE FIX, without pulling the heads:

1. Order a few slider push rod tubes from CB
http://www.cbperformance.com/catalog.asp?ProductID=120
2. Pull the valve cover and remove the rocker arm assembly.
3. Remove the push rod from the leaking tube(s) only.
4. Remove the leaking push rod tube(s) - just pry them out.
5. Put new end seals on the new (slider) push rod tubes
These are a pair of telescoping tubes with a spring inside and O-rings between the two telescoping ends. You compress them to install between the case and head, then let them expand into the holes on both ends. I've used them in the past, and have not had one leak.
6. Goop up the end seals with Blue RTV
7. Compress the tube and insert the ends into the appropriate holes in the case and head, then let it expand while centering it in the holes.
8. Re-insert the pushrod, re-assemble the rocker arm assembly.
9. Re-set your valve clearance (might as well do both sides of the engine)
10. Replace the valve cover with a new gasket.

Go have a Guinness.......Overall time for one tube; 30 minutes

Yeah - guess I was a loose stud in my younger days - old F#$t now! Worse case always comes to mind - when it often is simplist!

Is possible they put a dent in one -- and then to cover it us --- (or they saw a dent in one) and turned the tube with dent up so you wouldn't see it --- causing the existing seal to break and it leak. Aren't those tubes covered by a heat/cooling shield from the bottom?

A hidden advantage on the T4 (I guess) as you can replace the tudes without removing the heads.

Desi, when you say the push rod looks "crooked or not in line" are you refering to a single push rod tube that looks out of parallel with the other three, or are you thinking all four look crooked or out of square relative to the cylinders.

If it is the later, then that is normal. The holes in the head are a little bit offset from square to the holes in the case. So when you look at the push rod tubes they are noticeable crooked in relation to what you would think is "square".

Mark

The fix that Gordon discribes sound like the best bet,went down to V-Parts and pick-up the repair tube, I'm on it tomorrow, Mark thanks for the info on the alignment question. Wolfgang the loose stud - that's funny. Cabanaboy

Gordon's got it, as usual....I would add, "Rotate the engine by hand several revolutions after setting valve clearance, and recheck valve clearance." This insures a properly seated push rod....

Just a thought...

one other thing I discovered that makes pushrod tubes leak like crazy is a piece of bad fitting tin on the bottom side of the engine. I fitted a set of "cool tins" on my engine, dropped in a set of JayCee tubes, did sealant on the rubber grommets, set up the heads, and lifters and so forth. Everything was nice and snug, all is well, right? I had more leaks than a cheap garden hose. The cool tins did not fit as they should and created a SLIGHT pressure and resultant miss alignment on the tubes.

After I pulled the engine, not once but twice in search of the leaks in a couple of the tubes, did I find the real problem. After properly fitting the tins....yes, and pulling the heads, I used CB P's big mouth tubes, sealant on the rubber grommets, did I get the problem solved.

I also had a slight leak out of the fitting for the remote oil cooler that looked like leaking pushrod tubes another time....by the time the fan pushed the oil around the block...big mess, hard to properly troubleshoot....

If a pushrod tube is leaking and it's on the side where I replaced the head studs, you didn't have to get opinions from the group, all you had to do was to contact me.

I would warranty that problem.

no hating.. Larry, last we talked you mention you didn't want to do work for me, I'm glad your in agreement about the warranty issue, I have a qualified (25yr. +) mechanic 3 miles from me your 40 + miles from me. Cabanaboy ~ Livin La Vida Loca!!

I'm sorry but I don't understand the preface to your last post

You start out by saying "no hating.. Larry,"
I don't understand what you're trying to say here.


If you've developed an oil leak, and it's from a pushrod tube/seal that I installed last September, I'll repair that leak.
All you had to do was call to find out that I would make the repair.

In all fairness, if you choose to pay someone else to make the repair then you're on your own as I can't take responsibility for their actions.

Desi,

I forgot to mention this.

Unfortunately, I didn't see this thread until this morning. Had I seen this when you started the thread, I would have let you know then that I would warranty the oil leak if it was from the work I performed.

It only costs a few bucks to drive up here and if you wait, the total time is only about 1 hour.

Your mechanic will charge you labor and parts to make the repair. Your investment here is minimal.

But, it's your choice.

Thanks Larry, I'll consider your proposal.
No hating is slang for - no disrespect , now if I were dissing you ,now that's another story. Cabanaboy