81 caddy leaking diesel fuel from pump

[914rrr]

I noticed a 2 puddles under my caddy the other day.

One seems to be a leaking coolant hose or maybe a water pump on it's way out.

I thought the other was oil untill I smelled the puddle and it smells like diesel. The pump itself is dry on top, but wet on the bottom. Caddy has about 150,000 miles on it. The upper rubber lines and the return lines have been replaced and look dry.

I thought that maybe the pump seal was going until I read some other posts here that said that the main seal usually sucks air and doesn't leak. Is this true, or are there exceptions? Where do these pumps typically leak fuel from other than the main seal? If the pump seal is in fact bad, is the seal replaceable or is is it better to just replace the pump?

[BlackTieTD]

did you check the tightness (or possibly... looseness) of the hard lines going to the injectors? they can work themselves loose and when they do they leak fuel. try to clean up the wet area, spray it with brake clean to get it nice and dry, and then run the car and see if you can spot the leak's origin.

[914rrr]

Thanks for the tip. Tried drying off the pump with brake cleaner and running it. The leak isn't coming from any of the hoses or high pressure fittings. It looks like it's leaking somewhere on the bottom of the pump. Any ideas as to the source of this leak and / or a fix would be greatly appreciated.

Thanks!
Rob

[type53b_gtd]

The front seal on the pump can leak fuel, however it will generally not do so while the engine is running - rather it will leak fuel from the pump cavity when the engine is off, causing long cranking times while the pump "re-primes."   I have had the seal go to the point that the engine will not stay running because of the resulting air leak.

Leaks from other points at the pump (generally around the timing advance mehcanism shaft and cover, but also at the accelerator shaft or idle control) are usually a result of a blockage or excessive restriction in the return llne to the tank, which causes excess fuel pressure in the pump.  On early cars without check valves or fuel filters with recirculation valves, suspect a  kinked or blocked return line,  or a blockage in the calibrated orifice in the bango bolt on the pump side.  On later cars with check valves (A2 and up) or recirc valves in fuel filters (llate A2 and up) suspect either a bad check valve (located near the top of the tank) or a faulty heater valve in the filter, in addition to a kinked line or blocked calibrated orifice.

HTH,
Drew

[914rrr]

Thanks for the info. Looks like the pump main shaft seal is bad, as it now leaves a pretty good puddle after sitting overnight and is cranking a long time to start cold. Runs / starts fine after it has been run awhile.

An old friend of mine in KY who owns an import repair shop is sending me a NEW VW diesel pump to look at /size up. He's not sure what year it's for, but it's probably a newer one than what's on my '81 as it has the electric enrichment vs. the manual lever. Anybody run into any fitment /installation issues with this newer pump on a earlier (81-ish) 1.6 NA diesel?

He's also sending me a new pump main seal and the o-rings for the side covers just in case the old pump is resealable. The mechanic I normally use here in FL is willing to try resealing the old pump. He told me at 150,000 miles  the pump may be shot and the reseal may be a waste of time. What kind of success or failure have you guys had with resealing old pumps?

Any advice would be appreciated.

Thanks!

Rob

[914rrr]

Received the new pump (86 Golf pump) but it was damaged in shipment. Too bad, as it was a hell of a deal (<$500). I really wanted to have Giles do the pump rebuild, but time was short and had my local mechanic send out my old pump for a rebuild. I can't beleive how much more power it has after the rebuild, but it smokes waaay more than it did before. Is this a common situation with rebuilt pumps? My mileage actually improved after I changed my driving style. Before the rebuild I would wind out every gear to get moving, now I shift at low rpms. I love not having to turn off the AC when climbing hills and can go 75mph without going downhill.