Push Rod Tube Seal Leak Options

[collinvon]

Looks like I found where all the oil has been coming from. I cleaned the engine as well as I could with a degreaser, ran it for 5 minutes at idle, and was able to spot a substantial leak coming out of the push rod tubes:
(IMG:http://www.914world.com/bbs2/uploads_offsite/i.imgur.com-23207-1560976029.1.jpg)

I'm going to tackle this project this weekend. I've found some good older articles that mention it can be done without dropping the engine, but might have to replace the seals on a couple without fully removing them.

I'm going to replace the valve cover gaskets, adjust the valves for the first time, and I'll being doing the first oil change since I've had it. I've heard Valvoline ZR1 20W-50 is a good oil to use, and I can find it locally. Thoughts?


Aside from ensuring I don't damage the seals on reinstallation, and thoroughly cleaning everything, anything else I should keep in mind, or try to tackle while I'm in there? Any other tips and tricks are much appreciated.

Thanks in advance for any feedback.

[JawjaPorsche]

Excellent oil. Get newer seals such as viton. It can stand the heat better.

http://www.autoatlanta.com/Porsche-914-Vit...l-Kit-srch.html

[mark04usa]

Be sure to clean the push rod tubes and the bores really well and lube the new seals with oil on installing. Some folks will tell you to use a sealant on the o-rings. This has been debated here several times. My vote is no sealant because of the expansion and contraction of our engines from cold to fully warm moves these seals in the bore.

You won't be able to fully remove all of the tubes and it is a tight area to work in. Be sure your car is well supported by safe stands. (IMG:style_emoticons/default/smash.gif)

[dr914@autoatlanta.com]

it is a very nice filthy greasy mess to do, and will make you appreciate your 914 more once accomplishing it. Please make sure to check the valve adjusters for pock marks

[iankarr]

(IMG:style_emoticons/default/agree.gif)
If you've never done pushrod tubes before, I'd recommend dropping the motor. There will be a fair amount of blind wrenching, cleaning and head scratching geometry and if you're unfamiliar with how it all goes together, you'll have an easier time and learn more with the engine out. It will also give you an opportunity to change the oil cooler seals, do a full cleaning, and see if there's anything else that needs attending to. Also, if the PO used a sealant in the bores, it will be difficult to fully clean them while under the car.

In addition to the viton seals, spring for a set of new tubes. They're not expensive and you'll know they're all round and not dented (IMG:style_emoticons/default/wink.gif).

Good luck and be safe!

[collinvon]

(IMG:style_emoticons/default/agree.gif)
If you've never done pushrod tubes before, I'd recommend dropping the motor. There will be a fair amount of blind wrenching, cleaning and head scratching geometry and if you're unfamiliar with how it all goes together, you'll have an easier time and learn more with the engine out. It will also give you an opportunity to change the oil cooler seals, do a full cleaning, and see if there's anything else that needs attending to. Also, if the PO used a sealant in the bores, it will be difficult to fully clean them while under the car.

In addition to the viton seals, spring for a set of new tubes. They're not expensive and you'll know they're all round and not dented (IMG:style_emoticons/default/wink.gif).

Good luck and be safe!

Thanks for the great info. I have some viton seals on the way. I'm hoping to avoid dropping the engine for another couple of months, if at all possible. I plan to drop the motor, change all the seals/wearable parts, and see if anything else needs repair/replacement this fall while I repair some hell hole rust spots.. I will definitely be replacing the tubes themselves this fall as well.

If I have too much trouble, it looks like it's not too terrible to get the engine out. Getting it back in the first time is what is a bit more intimidating to me.

That being said, if it can be done with the engine still in, what is the best product to clean everything up with in there?

[iankarr]

If you're under the car, don't use anything too mind altering. Mineral spirits is probably as hard core as I'd go.

[Mark Henry]

To do them without dropping the engine you can remove the shift rod, loosen or remove the clutch cable, etc, then undo the front mounts and drop the nose about 4-6" . PITA on jack stands but doable, I have a lift and use my tranny jack to do this.

I use Dow 55, it's a mil spec O-ring lube, I used to use liquid teflon or even oil, I don't like putting them in dry.
Heads off I use a 120g drill flap wheel to to clean the head bores, on a rebuild I also do this on the case bore, but not on a assembled engine. With some sandpaper or scotchbrite pad make sure the bore openings have no sharp edges. Everything spotless clean and degreased.
As I put the PR tube in I spin the tube 1/4- 1/3 turn as I install, this and cleaning up the bores is so you won't cut/nick the seal as you install.

Double check that the PR tube retaining springs sit correctly, Likely you'll have to use needle nose pliers to pull them out so both corners sit on the PR tube edge correctly.

Oil, you're in minnesota, cold spring/fall mornings, so I'd recommend 15w40.

[collinvon]

If you're under the car, don't use anything too mind altering. Mineral spirits is probably as hard core as I'd go.

Sounds good. The more I think about it, the more I do just want to pull the engine and do everything right once. Seems to be easier to make sure I don't screw anything up if the engine is all the way out..

[collinvon]

To do them without dropping the engine you can remove the shift rod, loosen or remove the clutch cable, etc, then undo the front mounts and drop the nose about 4-6" . PITA on jack stands but doable, I have a lift and use my tranny jack to do this.

I use Dow 55, it's a mil spec O-ring lube, I used to use liquid teflon or even oil, I don't like putting them in dry.
Heads off I use a 120g drill flap wheel to to clean the head bores, on a rebuild I also do this on the case bore, but not on a assembled engine. With some sandpaper or scotchbrite pad make sure the bore openings have no sharp edges. Everything spotless clean and degreased.
As I put the PR tube in I spin the tube 1/4- 1/3 turn as I install, this and cleaning up the bores is so you won't cut/nick the seal as you install.

Double check that the PR tube retaining springs sit correctly, Likely you'll have to use needle nose pliers to pull them out so both corners sit on the PR tube edge correctly.

Oil, you're in minnesota, cold spring/fall mornings, so I'd recommend 15w40.

Awesome, thank you for the tips. Sounds like pulling the engine might just be the way to go.

[iankarr]

It's not as intimidating as it sounds/seems. I made a video outlining the steps and the link is in my signature below.

[collinvon]

It's not as intimidating as it sounds/seems. I made a video outlining the steps and the link is in my signature below.

That's a great video, I'm sure I'll be referencing it the entire time. Anything else I should check or replace while it's out? So far i'll be doing the following:

Replace push rod tubes/seals
Replace oil cooler gaskets
Oil Filter
Check oil sump filter (I ordered a new one JIC)
Replace valve cover gaskets
Adjust valves

[914Toy]

(IMG:style_emoticons/default/agree.gif)

[JawjaPorsche]

Get valve cover gaskets from 914Rubber. They make thick ones and they don’t leak.

Also since you have to remove shifter rod, I would replace bushings.

[iankarr]

...and check to make sure the front main seal and pressure sender on top of the engine aren’t leaking. Glad you found the video helpful!

[Superhawk996]

If you're under the car, don't use anything too mind altering. Mineral spirits is probably as hard core as I'd go.

Sounds good. The more I think about it, the more I do just want to pull the engine and do everything right once. Seems to be easier to make sure I don't screw anything up if the engine is all the way out..

(IMG:style_emoticons/default/biggrin.gif) good call (IMG:style_emoticons/default/beerchug.gif)

[porschetub]

I've only ever changed one set with the motor out of the car (not a 914) and found the old ones were viton and covered in a red sealant,I couldn't buy replacements @ the time so I visited a friend who ran a Eaton Fluidpower franchise and we sized hydraulic grade orings to suit,I had no leaks,these orings have a higher temp rating than viton ,don't remember the hardness rating but we found ones that matched the originals.
My guy said never fit them dry,some sealer is ok on T1 seals but not on a T4 as there is movement as mentioned.

[IronHillRestorations]

I also clean the bores, inspect for nicks and gouges, and use a Scotchbrite pad to gently scuff them circumferentially. and clean again. I stuff a piece of lint free disposable cloth in the lifter bore to keep abrasive from getting in. I use a thin coating of Loctite 565 right before installation. It helps lubricate the O ring and seal them. I do one tube at a time.

I've seen some guys goop them up with RTV, but that's not a good idea as it limits the thermal movement and can cause leaks.

Make sure you get the retaining wire in correctly or you'll ruin the push rods and potentially kill your engine.

[collinvon]

I also clean the bores, inspect for nicks and gouges, and use a Scotchbrite pad to gently scuff them circumferentially. and clean again. I stuff a piece of lint free disposable cloth in the lifter bore to keep abrasive from getting in. I use a thin coating of Loctite 565 right before installation. It helps lubricate the O ring and seal them. I do one tube at a time.

I've seen some guys goop them up with RTV, but that's not a good idea as it limits the thermal movement and can cause leaks.

Make sure you get the retaining wire in correctly or you'll ruin the push rods and potentially kill your engine.

Awesome, thanks for all of the info. Any tips on ensuring I get the retaining wire back in correctly?

[IronHillRestorations]

It's pretty straightforward, just be sure to see how it's in there (pics prior to disassembly help) and make sure it goes back in correctly.

It's basically held in the slot on the rocker shaft bracket by spring pressure, and keeps pressure on the end of the tube. In doing my first rebuild a few years ago (35) I mistakenly trapped the spring under the rocker shaft bracket and was fortunate to find the problem before it killed my engine.