Hello All, I do have two question for the experts and hope you can help me there. I have fully reconditioned my 250 Gte engine and now have it running on a small self build test rig - see photo. It is running fine but after some time water started to come out of the seep hole of the water pump. I overhauled this with a kit from GTO and they said they use this without problems. I did therefor not use the old spring as recommended in other threats. Now that I have to do it again I was wondering if you have experience with the update kits available using the latter seals from 365. I know there are conversions from Bell Classics and Roeloefs. Any experience or recommendations? The second question is about removing the pump: do you slacken the cam chain tensioner before dismounting the pump? I would guess so but would like to know what the experts do? I am not sure how much strain the chain puts on the shaft when the water pump is dismounted. It is clear to me the dismounting has to be done carefully to make sure the shaft with bearing at the end stays in the chain housing. Any hints welcomed. Thanks a lot. Christopher Image Unavailable, Please Login Image Unavailable, Please Login
I don’t have much to offer for you Chris, but just recently ran into a problem with water pump service parts readily available for 365 GTB/4. The new (reproduction) WP impeller spacer/shaft seal sleeves* for this application appear to be made incorrectly requiring 2 different re-machining procedures to make the useable. You might want to check if 250 like yours uses same/similar spacer/sleeve and if they do, closely compare to original one. *I had two in-stock, bought within last couple of years from different well established, long time vendors, although both are/were in identical (sealed) packaging with identical part number labels, so presumably from same supplier. P.S. I’ve bought/replaced these over the years, but never experienced this problem before, so I assume it’s more recent issue.
so you used new spring or no spring? without spring the water pump has to leak you not have to remove the complete pump, only the front housing and the propeller, then you reach all and not have to loosen the chain tensioner what is the black round box left of the electric fuel pump for? how much bar the fuel pump makes? what car is this in the second photo with the spoke wheels? looks like a british car?
I would use a waterpump from Modena Motori. Or at leat their gasket set. No problems with their parts. With other parts suppliers I had not so much success.
Timo, Romano, Mechaniker, Thanks for the answers. I will talk to Modena Motori, know them from Padua fair. To the questions of Romano: - yes, used spring supplied by Gto - black box is my strobe - electrical fuel pump has max. 5 psi/ mechanical not used at the moment in this setup. Will mount and check it as soon as everything else is perfect - Triumph TR4A I am still interested if there is experience with the kits from Roeloefs or Bell? Thanks Christopher
Go to internet and research: “Crane seals” for impeller shafts... Almost ZERO car manufacturers make stuff like this-they all buy it from vendors: think tyres, carbs, distributors, dynamics, starter motors! That said, it’s just a series of dimensional constraints, spring coefficients etc... they are cheap from genuine suppliers Avoid made in China-liability issue(while generally fine, statistical failure rates fall outside allowable norms IMO), which means twice as expensive in most cases. ALL the parts houses are doing this: NOBODY has these things “made for us”, strictly off the shelf, manufacturing supply chain stuff....
I stopped using the standard 250 waterpump seals 25 years ago. I convert all my V12 waterpumps to using a 308 2 piece seal I believe it is the same or similar to the 365GTB4 set up. Never have had a problem since.
I now have a Roloefs pump conversion. To mount this the complete old water pump has to come out without disturbing the water pump shaft. I got lots of advice about using a pump with daytona style conversion from Dyke. Thanks again. I build myself a simple tool to fix the shaft while dismantling the pump. See pictures. Worked fine. Christopher Image Unavailable, Please Login Image Unavailable, Please Login