Gaskets, which ones?

[bnk999]

1974 chrysler 75hp --757HA<br />I am replacing my impeller and my powerhead (costly mistake ) and have some questions on gaskets needed. First of all when I replace my impeller, do I need to replace the driveshaft seal that sits in the top of the water pump housing? Second do I need to replace the water line tube seal that is on the top of the water pump housing? Also do I need to pull up the plate underneath the impeller for any reason and replace that gasket? Also when replacing the powerhead it appears that I need possibly the upper and lower kingpin gasket. (thanks eurolarva) I have been having a hard time finding these gaskets, can I use some type of gasket maker in place of these or does anyone know where I can find these? <br />Thanks

 

[eurolarva]

Re: Gaskets, which ones?

I would buy this set 18-4313 is the part number. NAPA may show this part number but they may not have it in stock. IF not go here 30 bucks seems pretty good price. The Shad Connection <br /><br />I tried to make my gaskets for above and below the kingpin but the thickness is critical. It also has to be a thick enough gasket material so it wont blow through. I think the grommet for the water tube is included with the kit. If your lower unit is not leaking dont mess with the drive shaft seal. Most chryslers do not have a seal for the water pump to the stainless steel plate. You can replace the plastic pick up tube on top of the water pump that the brass water tube connects to but if it is in good condition I would not mess with it.<br /><br />Key things with the new head. Run gas mix at 24 to 1 for first six gallons of gas and take it easy on the motor. Make sure the link and sync are done right and that mixtures are set perfect or slightly rich. Check the water coming out of the telltale and make sure the water is very warm or tepid. <br /><br />As I said if the lower unit is showing so signs of water getting inside do not mess with it till you have broken in the powerhead and everything is running right. If you have problems you will want to focus on one part of your motor. By rebuilding the lower unit and replacing the head at the same time it is going to be hard to figure out where your problems are coming from.

 

[eurolarva]

Re: Gaskets, which ones?

Oh yeah get some permatex that does not harden for the kingpin gaskets. If you have to take that head off a week later you will be glad you did. NAPA sells one in a can with an applicator brush I believe was for aviation use.<br />Good luck

 

[bnk999]

Re: Gaskets, which ones?

Thanks eurolarva, I was actually able to get the upper kingpin gasket from mercruiserparts they called it the upper exhaust gasket, will use permatex for the bottom-