1978 70HP Fuel Pump replacement

[azbrewer]

I replaced the diaphragm and checks on my 70 HP 3 cyl.fuel pump. However the instructions say to also change the transfer port cover if it does not have a raised casted pad, well my don't. I have searched for this and it seems to be an obsolete part. It runs as is, should I just forget about it?

 

[Chris1956]

Re: 1978 70HP Fuel Pump replacement

I would leave it alone. After all it has worked for 30 years as is. There were some differences in fuel pumps over the years. Perhaps the manual is confused or able to confuse it's reader.

 

[azbrewer]

Re: 1978 70HP Fuel Pump replacement

I no choice but to rebuild the fuel pump, as the motor would occasionally stutter and pumping the bulb would stop that. It would require pumping the bulb after shutting off the motor to get it to restart, even if off for only a few minutes.

 

[Chris1956]

Re: 1978 70HP Fuel Pump replacement

I guess I do not understand why you would need to replace the transfer port cover on your motor. There should be a fuel pump kit available for the transfer port cover you have. There are at least two different kinds of fuel pumps. One mounted on the transfer cover, the other mounted on the lower cowling, and had hoses to the transfer cover pipe nipples. There are differnt rebuild kits for each type, but you do not need to change transfer covers.

 

[azbrewer]

Re: 1978 70HP Fuel Pump replacement

The rebuild kit I bought is the only one available at the only parts house here. I could not read the instructions until the package was opened and now it is non-returnable. There is a spring now behind the diaphragm that may stretch the diaphragm unless the raised casting is on the cover to limit the travel. The kit came with 2 gaskets for what looks like a spacer plate between the pump and cover, however I can?t find anything in any parts book or list. The motor runs with the rebuild as is but I don?t know if it will fail in time.

 

[Chris1956]

Re: 1978 70HP Fuel Pump replacement

Rebuild kits for fuel pumps are vey cheap$4-6. You might visit a Merc dealer and make sure you have the correct one.