TOPIC: Replaced powerhead??

I got to looking at the "62" Johnson I put on the aristo the other day and was noticing some things. One was the id button on top of the left cylinder bank looks to have been removed and reinstalled and also the paint on the intake looks like it 's older than the paint on the crankshaft cover. Also where the paint has came off of the block there is a brownish red primer. Has anyone ever ran across a factory powerhead replacement and is what I've described sound like it could be one?? Or am I way off on this? Any thoughts?

I'd say you're probably on the right train of thought there Jim. It appears that somebody has been into that motor before, IMHO. (Shouldn't be an issue, if it's running well they must have fixed it properly, right!?)

I'm not sure when they started using it, but the 70's OMC motors I'm familiar with were painted (at the factory) with temperature sensitive paint. They were originally blue/green (?), but turned dark red if the motor ever overheated. May not be the case with the 60's motors, could just be red oxide primer? The two different shades of white definitely suggest it's been apart before, for whatever reason.

Just my humble ramblings, hopefully one of the gang who really knows can advise further.......

My 73' 65HP has the red primer where the paint is missing. I don't know if Mark's paint color changing theory is true or not, but I did suspect mine had over heated and the lower compression cylinder had the most paint missing. Personally I believe the primer was just rust colored red.
I also had a 69' 9.5 that showed some red primer as well.
Both engines were/are fine though.

Guys,my thinking is when I first got the motor I had to touch up various places on the block where the paint was scaled off and noticed how clean the block paint was. The paint is not adhered too well to the block like it was painted a good while after it was primed. I think I remember someone here saying that factory replacement blocks came red oxide? primed. That's my theory, fwiw

Jim

OMC used the Red oxide chromate primer on all the engines. The final color was determined by which line the engine was on. The welch plug on the water jacket will be stamped with the serial number matching the ID tag on the outside of the engine. The Johnson engines had a little Seahorse image on the plug, and the Evinrude had either an "E" or the evinrude name.

A factory replacement power head will have a plain welch plug stamped with the letters R.P.H. These engines were only oxide red, and the dealer either installed it with no final color or it got a rattle can paint job top match the motor color.

The intake manifold on your engine could be simply stained by 50 years of weeping fuel. That is very common to see them stained like that. And the top color paint often flakes off in spots, even on some NOS examples.

Bruce, what did you ever do with that RPH powerhead you got from me 10 years ago or so? That one was red oxide.
Geez, that was a long time ago now that I think about it. We are old........

Bruce, what did you ever do with that RPH powerhead you got from me 10 years ago or so? That one was red oxide.
Geez, that was a long time ago now that I think about it. We are old........

Damn, Bill..... Don't mention age or years passing like that! And yes we are old, because that RPH I got from you is actually GOLD. Someone painted the gold over the red oxide, so you are still OK though.......

As for the engine, I'm ashamed to say, is sitting. I'm letting it age like a fine cheddar cheese. I bought my house just after getting that powerhead from you, and then I got distracted with more projects (wow-imagine that)

But, never fear - it will find a home at some point.

Hope all is well in Seattle.

BG