1968 Lightwin powerhead compatible with 1958?

[pdpantages]

Hello forum,

I have an Evinrude 1958 Lightwin 3HP model 3026 that I inherited. I think that the motor had been dunked; it was seized. Cylinders, rods and crank damaged etc.

I am pretty sure the block is not salvageable and have been looking for a replacement powerhead. I have found one that is from a 1967 or 68 motor. Would this powerhead be compatible with the 1958?

I looked in marineengine’s parts diagrams and can see that the 1958-1968 use the same crankshaft for this motor (part #0203555). So no problems with the flywheel fit or driveshaft splines. But the crankcase part number changes after 1964. The part numbers are 0379436(1958) vs 0381821.

I can see from the parts pages that the 68 introduced a fuel pump. I can see some extra threaded mounting holes in the new powerhead that must be for this.

One difference I see in the parts drawings is the powerhead mount. The 58 had an inner flange #0203145 and gaskets #0203161,0203160. The 67 replaces the flange with a powerhead adapter #0382071 and gasket #312946. The 1968 parts diagram does not show the adapter, just the gasket.

It looks to me that I could put the 58 flange and gaskets on the 68 powerhead and mount it. Note that I don’t have physical possession of the 68, but I have pictures I can refer to.

Does anyone know for certain that a 68 powerhead would work, with or without modifications?

Thank you for any info, PdP

[1946zephyr]

Yes. I believe the Lightwin/JW powerheads are all interchangeable from 1952 to 1967. 1968 was a fiberglass hood model and is likely different. So you should be good to go. Its really easy to check it. Compare part numbers on the base gaskets too. That is the truth teller right there.

[pdpantages]

Thank you zephyr.

I can see that the crankcase part# for the 67(and earlier) and 68 are the same. So they must be interchangeable as far as the tank/cowling mounting goes.

By base gaskets, are you referring to the powerhead gaskets? There are some differences I noted in my post, but it looks to me that new powerhead would be "backwards compatible" with the older inner flange + gaskets. As far as other gaskets go, I have looked at an assorment; carb, manifold etc. and all look to be matched.

[fleetwin]

Sorry, but the crankcases are different from 58 to 68. The crank, pistons, rods are the same though, if you can salvage your crankcase.

[pdpantages]

Thank you fleetwin. I don’t think my crankcase is salvageable. At a minimum I would need to bore it out and get 0.020 over pistons :(.

[fleetwin]

Well, the original surely isn’t worth boring, so I am sure you can find a decent powerhead for your engine. Try webvertise, classifieds.

[pdpantages]

Here are a few pics of the hapless crankcase….

IMG_0100 by pdpantages, on Flickr

IMG_0101 by pdpantages, on Flickr

IMG_0102 by pdpantages, on Flickr

[Steve A W]

That poor little motor 🙁
Lucky thing is, there were lots of them made. 😀
Good luck with you motor.

Steve A W

Member of the MOB chapter.
I live in Northwest Indiana

[fleetwin]

Yeah, nothing can be saved there….Spent some time under water, then left to rust away, too bad.

[outbdnut2]

RIP! Rust In Peace!

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