1975 Evinrude 25hp, need cylinder head, what years work?

brockj · #1 July 9th, 2008, 11:30 PM

Hi all!

I have a 1975 Evinrude 25hp, after a little work she was running good, until the upper spark plug hole got cross threaded, so I need to replace the cylinder head now. I was talking to someone and got a cylinder head from a 1972 Johnson 25hp, that was supposed to work, and though it looks like everything lines up properly, there is no where to mount the coils! So I am wondering what years/hp's would be a compatible replacement for this motor?

Thanks in advance!!

Kflc · #2 July 10th, 2008, 02:44 AM

hi there, you should be able to get a threadsert/ helicoil installed, especially if it takes 1/2 inch plugs. You will then not need a new head. You also do not need to remove the head to have it done as the motor will spit out the swarf when it starts.

brockj · #3 July 10th, 2008, 08:11 AM

Thanks for the reply. I actually did have that done, (well I did it myself), and it did not stay. It worked fine for a few outings, but my last time I used it, it blew the spark plug and insert right out of the head! Thankfully I had an electric trolling motor to get back to shore, but have not used it since.

Quote:

Originally Posted by Kflc

hi there, you should be able to get a threadsert/ helicoil installed, especially if it takes 1/2 inch plugs. You will then not need a new head. You also do not need to remove the head to have it done as the motor will spit out the swarf when it starts.