Fuel pump push rod sticking in Bakelite guide

[1966novacoupe]

The fuel pump push rod just started sticking in the Bakelite guide in my mostly original 61 beetle.. Been running great til now. After the engine warms up the push rod sticks in the Bakelite guide at the top of its travel and of course the car shuts down. As soon as the engine is completely cool it works fine again. Is the push rod lubed by an oil passage that may be plugged? I had to use pliers to remove the push rod from the Bakelite. The rod had some score marks on it [ i think normal for 62 years of running ] i dressed the rod up with 1200 grit wet/dry. It cleaned up very nicely. A little grease on it and it slides easily up and down. Do i need to replace the Bakelite guide and push rod Or clear an oil galley? Thanks for any info. Steve

[67rustavenger]

Steve, This subject was discussed tonight in the thread pasted below.
https://www.thesamba.com/vw/forum/viewtopic.php?t=393158
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[Cusser]

[1966novacoupe]

Thanks for all the good info. I completely agree, if its not broken dont fix it. The push rod had some wear marks and Galling spots on it which is why i asked if it was oil fed. Appears its not, but then with only 4mm of travel with each rotation of the distributor it wouldn’t need a lot, especially with a hardened steel push rod inside a Bakelite holder. Generally dirt or grit will stick in the softer of the two surfaces. In this case Bakelite then wear on the harder part which is just what happened. When the two parts swelled a bit with heat the pushrod would stop at the top or end of its travel and stop activating the fuel pump. With the rod polished to a mirror finish and a bit of grease the push rod slides to the bottom of the travel Easily. Ran the car yesterday for an hour. No issues at all. Fuel pressure at a constant 2.9 psi. Ive ordered a new push rod and fuel pump spacer block/push rod guide. Ill keep the parts on hand so IF this happens again ill go ahead and replace them both. I like the idea of tapping the the broken part of the guide [if it breaks] 3/8 16 then using the same all thread and washers and nuts to draw the broken part out. Seems easy enough. Ill repost when/if this happens. Thank you so kindly.

[kreemoweet]

If the rod had score marks, the plastic stand probably has hard grit embedded in it, and should be replaced. The rod has considerable force on it when it's in its highest position (from the main diaphragm spring and also a separate return spring), so a seizure at that point is no small matter.

The fuel pump stands do have an oiling hole in the side, about halfway up, to allow for splash lubrication [EDIT: they actually have 2 holes]. The rod itself also has a narrowed section at that level, which makes a storage compartment for the oil.
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[1966novacoupe]

Thank you kreemoweet. I agree on all points. Since there was no oil in the center recess area of the push rod when i removed it i would assume the oil passage hole is at minimum, partially blocked. Since my car is not a daily driver, [i dont depend on it for transportation] when the new parts arrive ill change them both. I think I’ll warm the engine completely first then give the Bakelite stand a couple shots of refrigerant to try and shrink it before attempting removal. If it still breaks, theres the 3/8 16 tap!

[1966novacoupe]

Well all done, warming the engine and freezing the Bakelite spacer only made the spacer more brittle. After it broke off i tapped the hole 3/8 16 and removed the rest of the broken parts with a piece of all thread. Took about an hour for everything. Removed the oil screen. Flushed 1 quart of new 5w30 oil down thru the spacer block and distributor hole just in case of any small pieces of Bakelite but i didnt see any. Cleaned the screen new gaskets, new spacer and pushrod new fuel hoses and clamps and the car is running great again. One side note. The fuel pressure is a constant 3 psi. Before it would fluctuate 2 to 3 psi. I’m guessing because of the sticky push rod. Thank you samba members for all the great advice.

[Cusser]

Great job !!!
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