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leaking push rod tubes (seals)
oval TOFU - January 19th, 2006 at 09:45 AM

yup, they are leaking all over my heater boxes. Should I replace just the seals, or the whole tube and the seals? On one side, the tubes look 'new' (they still have the stickers on them) but the other side look a bit old...

what to do.. what to do...

DIY-DUB - January 19th, 2006 at 09:50 AM

whole lot at once if the $$ is available, easier in long term in my op:tu:

blutopless2 - January 19th, 2006 at 10:27 AM

replace the lot.... at least then you KNOW that they are all new tubes and seals.

oval TOFU - January 22nd, 2006 at 02:07 PM

cool, I've ordered new stainless push rod tubes :)

I read in the manual that I should replace the gasket of the head-to-cylinder join. I suppose this is a good idea?

76camper - January 22nd, 2006 at 02:26 PM

If your taking off the head then why not. Good time to check deck height and compression aswell or if your happy just run with the same size gasket as before. Good luck with it.

oval TOFU - January 22nd, 2006 at 02:36 PM

The compression seems to be good (drives very well), so I'll probably just leave it. What's the deck height?

HGFS - January 22nd, 2006 at 10:07 PM

Quote:
Originally posted by oval TOFU
The compression seems to be good (drives very well), so I'll probably just leave it. What's the deck height?


The amount of space between the piston at TDC and the top of the cylinder. One way to measure it is torque down a cylinder with a piece of flat bar going diagonally across the cylinder. Rotate the motor until that piston is at the top of the stroke and measure the gap between the piston & the bar with feeler gauges. The measurement, the cc's in the head & the stroke is used to calculate compression ratio.

oval TOFU - January 22nd, 2006 at 11:35 PM

Quote:
Originally posted by SVW-054
The amount of space between the piston at TDC and the top of the cylinder. One way to measure it is torque down a cylinder with a piece of flat bar going diagonally across the cylinder. Rotate the motor until that piston is at the top of the stroke and measure the gap between the piston & the bar with feeler gauges. The measurement, the cc's in the head & the stroke is used to calculate compression ratio.


That sounds way above my head! If I do a compression test with the heads on and everything is ok (120psi give or take 10psi per cylinder?) I should be able to leave it all alone yeh?

oval TOFU - January 23rd, 2006 at 03:39 PM

Quote:
Originally posted by oval TOFU

That sounds way above my head!


oh dear... I just realised the pun.. hahaha

*did* - January 23rd, 2006 at 06:38 PM

maybe go some adjustable push rod tubes, then you dont need to pull your heads.
just unbolt the rockers, pull out the push rods, bend and remove the old tubes, put in the new ones (with new seals), push rods back in, rockers back on and away you go!

oval TOFU - January 23rd, 2006 at 06:53 PM

I've bought the 'normal' push rod tubes already... it's off with 'es head now! Besides, I haven't heard good things about the adjustable ones..

vw54 - January 24th, 2006 at 06:27 AM

what size engine are we talking about 36 40 1500 ???

The compression test sounds good however i would re lap the barrels to each head to be sure it seals properly, which also means removing each barrel and cleaning the heads n tops of pistons of carbon build up.

oval TOFU - January 24th, 2006 at 09:42 AM

40...

re lap???

vw54 - January 24th, 2006 at 10:49 AM

OK theres no head gaskets on any of the air cooled VW engines so you have to lap each barrell to each head position, just like lapping valves to the head

76camper - January 24th, 2006 at 06:41 PM

definantly worth getting rid of carbon deposits. save you from run on problems in the future aswell as pinging.

oval TOFU - January 24th, 2006 at 09:43 PM

Quote:
Originally posted by vw54
OK theres no head gaskets on any of the air cooled VW engines so you have to lap each barrell to each head position, just like lapping valves to the head


Sorry, I still don't know what 'lapping' is.. :cry

vw54 - January 25th, 2006 at 06:01 AM

You get Valve lapping paste which is an abrasive paste and apply it to the top of the barrell and insert it into the head then rotate back n forth to lap the faces together.

Its basic engineering as theres no gasket it makes the 2 surfaces flat so they seal when tighten up

oval TOFU - January 25th, 2006 at 09:43 AM

do you get rid of th paste once you they're lapped together? or leave it in like a liquid gasket kinda thing?

koolkarmakombi - January 25th, 2006 at 10:52 AM

http://www.valv-trol.com/lap.htm 

google is your friend

oval TOFU - January 25th, 2006 at 11:02 AM

this is scaring me..

vw54 - January 25th, 2006 at 01:56 PM

Wash the paste out throughly from all surfaces other wise it will bed the rings in and cause blow by