Technical Push rod tube oil leak
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Technical Push rod tube oil leak
I think there are too many joins and they are too fiddly to be able to successfully clean up and wipe on some sealant.
But it might be worth removing the rocker cover, thoroughly degreasing around the tops where the most accessible part of the tubes enter the head from below. Then put on a tidy and very thin wipe of high quality sealant.
The top of the head is swimming in oil when the engine is active. Although the leak could be anywhere, the top ones potentially are the worst.
Hi CF500, I note from your pic that you have a Panda head with the two-part pushrod tubes fitted. The problem you have is that as Peter says there are many parts and the problem could be at one or all of them!!!. You have oil pooling at the bottom of the top tubes and on the lower spring of the number one exhaust rod at least. Peters idea of using sealant is valid, But you must ensure that the area around the top of the tubes is spotless and degreased before attempting to apply sealant. Even if you remove the head (or engine) the difficulty does not stop as replacing the upper seals located within the head is difficult without damaging the tubes on removal. If you have oil pooling below the lower spring of the lower tube the join between them is leaking too. Luckily there does not seem to be much (if any) oil on the side of the crankcase (unless you have been cleaning?) You have to consider how much you drive and how much loss/mess is accumulated over time. The simple way would be to clean and degrease the top without contaminating the oil in the sump and try sealant, otherwise it's a sod of a job to correct all of the multiple leaks all of the time. You could damage the tubes at least and damage the head at worst, modifying the head for the VW tubes is also time consuming and costly. I did and my head still leaks slightly - it's a s**t design after all!!! any questions ask.
Ian.
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That’s a better reply than I expected I thought the 1st reply would be “No you have to remove the engine” I know that would be the right way.
Many thanks, as I said any help is welcome
Barry
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Ian Thanks for your advise I am taking it all in
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They say you learn something every day even at my age, Ian you have just told me I have a Panda head , dont know if thats good or badIan Thanks for your advise I am taking it all in
Barry
the hobbler
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One of the disadvantages of the Panda30 head, the 4-port head (the every other 500/126 head only has 3 ports--1 in + 2 out), is that 2nd joint between the top , short tube and the lower longer tube. The seal design is quite different as well; the top-tube's top seal is an 'O' ring IN the head, which over time hardens and stops sealing---and they are a bugger to get out and find replacements for! I have a spare set of top hoses if you need them as on the Panda30 head that I am fitting onto my 695SS engine, I have modified both the head and the VW adjustable push-rod tubes that I am going to use.
The advice given by peter, to clean off the oil and run a smear of sealer round the joints might, in the light of how few miles you do (which is a shame---use it and enjoy it) be the most sensible thing to do. Looking at your photos, there doesn't seem to be much of an oil-leak---are yousure that it is an oil leak and not just some squeezed out sealer?
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1st thing I will try is as Peters advise that is to remove the rocker & totally clean out any surplus oil , then hopefully find a paste that will withstand heat & obviously will not dissolve by the oil also try & seal the tops & bottoms of all ten tubes as per picture.. Would anyone be able to recomend a good oil sealer paste for this knowing the high temperature that it has to withstand. Thanks again for everyone’s advice.
Barry
Barry
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Permatex grey. Nothing else beats it that I've tried. Don't go mad with it.
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I keep learning every day, sometimes from the combined wisdom expressed here and sometimes from experience, good or bad.
the Panda 30 was a two cylinder 650cc aircooled version of the series 1 Pandas that were never sold in the UK. I have only ever heard of one being shipped here fairly recently. Called a Panda 30 because the engine produced 30hp, which is more than the 126. This was due in part to the improved twin inlet port cylinder head which worked in conjunction with a twin choke downdraught carb. The cylinder heads etc are much sought after in the Fiat world for tuning.
pictures show an original, your one has had the shape modified to suit the original tinware which is a lot of work but guys went to those lengths if enthusiastic enough. These days guys try to get the tinware from a German 126 (Bambino) which is very rare or modify existing tinware. The upper pushrod tubes are factory set in during manufacture and are not removable unless you hammer them out. Very unlikely that these will leak oil. The lower short push rod tubes are in the same style as the Fiat 500 and series 1 126. They use the same thin seals which are often the cause of oil leak problems.
I have got a load of those seals and some are as hard as a rock and some are still quite supple. Even the Haynes manual tells you that the tubes can be a problem if they get shortened due to pressure on them and talks about checks to carry out on assembly and to stretch the concertina sections on shorter tubes to get a matching set by working them from side to side which I now tend to as a matter of course these days.
Bad news is you can only fix this by refitting them. The guys that were supposed to fix your oil leaks must have been out of their depth I guess.
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Peter, thanks just been reeding up on Permatex it looks perfect, not only that they sell it in Bedford just round the corner from me
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Toshi, thanks, very interesting. believe it or not it was MBG in Bicester who removed the engine this time last year.
Am I correct in what you are saying the tubes shouldn’t leak from the top under the rocker? (or at least less likely) because that should make it easier to thinly apply Permatex around the top and bottom of the tubes.
By the way the guy that I bought the car from was an Italian living in South London, he owned it I believe from new, R/H drive removed the engine then went to Italy and had this engine built over there spent an absolute fortune on it and said he wanted to go as fast as his 911. It’s fast but not as fast as a 911 he fitted discs all round (waste of time) adjustable suspension, Oil cooler and that massive webber 40 DCO every thing was over the top!
Thanks again Barry
Oh MBG, that group of experts that managed to install a timing chain back to front so the self tensioning weights were gouging into the main bearing housing. I bought the engine when the owner gave up with it when it would hardly run and overheated badly. MBG did not want to know.
Unless those top tubes have been beaten about I don’t think they can leak oil. There are no seals on them.
Engine building is an expensive business these days especially with the cost of parts more than doubling in the last couple of years and the price of services like engine machining etc. as a couple of guys here can testify the cost of building a hybrid tuned engine can be out of this world, certainly never cheap. There seem to be less guys and gals around these days that are taking on rebuilds it seems to me. The last engine I sold less than two years ago was a crankcase up rebuild to a medium tuned set up and only driven for 1000 miles. Sold it for £1400 all complete and running on the bench. You could not build its equivalent today at that price just in parts.
I have kept a record of the parts used on my latest 540cc Nanni special build using new parts I already had so I priced many parts very generously and in parts alone the total is just short of £1900. A guy I know asked me to let him know when I had another engine ready as he missed out on the last one. I know he has Fiat cars to a value around £40,000. I pinged him a message to let him know, How much ? He said. I told him the cost of parts and I have never heard from him again
the hobbler
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The top (short) pushrod tube IS sealed---the seal for the top of that tube is a square (profile) '0' ring that its in a groove IN the cylinder head. The internal diameter of the seal is slightly less than the external diameter of the push-rod tube--the pressure on the seal applied by the push-rod tube by going through the slightly lesser internal diameter of the seal causes (hopefully!) the leak-tight seal. I know this because I am fitting a (suitably modified) Panda30 head onto my '695SS' engine and one of my jobs has been to scrape out the old, very hard seals and then find new '0' rings to fit into the groove that are sligtly smaller (internal diameter-wise) than the push-rod tube. I shall also be using the normal '0' ring seals on the top and bottom of the new (VW adjustable) push-rod tubes---hopefully it won't leak!Oh MBG, that group of experts that managed to install a timing chain back to front so the self tensioning weights were gouging into the main bearing housing. I bought the engine when the owner gave up with it when it would hardly run and overheated badly. MBG did not want to know.
Unless those top tubes have been beaten about I don’t think they can leak oil. There are no seals on them.
Engine building is an expensive business these days especially with the cost of parts more than doubling in the last couple of years and the price of services like engine machining etc. as a couple of guys here can testify the cost of building a hybrid tuned engine can be out of this world, certainly never cheap. There seem to be less guys and gals around these days that are taking on rebuilds it seems to me. The last engine I sold less than two years ago was a crankcase up rebuild to a medium tuned set up and only driven for 1000 miles. Sold it for £1400 all complete and running on the bench. You could not build its equivalent today at that price just in parts.
I have kept a record of the parts used on my latest 540cc Nanni special build using new parts I already had so I priced many parts very generously and in parts alone the total is just short of £1900. A guy I know asked me to let him know when I had another engine ready as he missed out on the last one. I know he has Fiat cars to a value around £40,000. I pinged him a message to let him know, How much ? He said. I told him the cost of parts and I have never heard from him again
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As I said previously I am going to use Grey Permatex on all the seals on the outside of the tubes at the base & top I intend to gently & finely spread the paste then use stainless steel self locking bands over the seal as an extra security. 
A couple of images from when I last did my engine...using the more flexible, red rubbers and Permatex sealant as backup.
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Well started cleaning the tubes, & trying to dry off any oil I 1st used brake cleaner then carb cleaner not sure which would evaporate any oil prior to me sealing each top & bottom tube. I will leave it for 24 hours then place a fine 2mm layer of permatex round each tube of which I intend to fit a stainless steel cable tie over the top of the permatex to keep it in place
see 1t image with s/s band in place before applying permatex. If it doesn’t work it will have to be an engine out job. I will keep you posted as this seems to be a common problem. still annoys me immensely after paying a so called professional that charged for the engine to be remove plus charged for a set of pushrod seal tube set which was obviously not done.
see 1t image with s/s band in place before applying permatex. If it doesn’t work it will have to be an engine out job. I will keep you posted as this seems to be a common problem. still annoys me immensely after paying a so called professional that charged for the engine to be remove plus charged for a set of pushrod seal tube set which was obviously not done.
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the hobbler
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I think that you will find that trying to keep the stainless bands in place on the curve at the bottom of the (top) push-rod tubes will not be easy. May I suggest that you first of all try seeing how it seals without the bands.Well started cleaning the tubes, & trying to dry off any oil I 1st used brake cleaner then carb cleaner not sure which would evaporate any oil prior to me sealing each top & bottom tube. I will leave it for 24 hours then place a fine 2mm layer of permatex round each tube of which I intend to fit a stainless steel cable tie over the top of the permatex to keep it in place
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Many thanks I will take your valid advice
Hi there. How did it go with the permatex grey, any success. I was going to try the same myselfWell started cleaning the tubes, & trying to dry off any oil I 1st used brake cleaner then carb cleaner not sure which would evaporate any oil prior to me sealing each top & bottom tube. I will leave it for 24 hours then place a fine 2mm layer of permatex round each tube of which I intend to fit a stainless steel cable tie over the top of the permatex to keep it in place
