3 hp 67 lightwin advice....

[Sea Raider I]

Gentlemen,

I came across this motor with a parts motor for $30, when I visited to check compression the whole motor seems to be siezed. We couldnt get the flywheel to turn at all. Owner claimed this motor ran last year then he just put it in the shop. Parts motor actually had 60 psi on both cylinders. I believe they interchange, but I just want to get that 3 hp up and running. Problem is I am a novice at 2 stroke motors. Should I just pass this up, or what am I getting myself into?

I also noticed that marineengine.com does not have the online parts manual to order from so that kinda makes me want to stay away from it. However, with your expert advice is this motor worth rebuilding?? All i need it for is to push my small 14' fg olympian around the lake...

Thanks in advance... BTW its model #3706c

 

[tx1961whaler]

Re: 3 hp 67 lightwin advice....

I'd go for it for 30 bucks. At marineengine.com, they have the parts lists/diagrams for the pre-1968 motors online. You just look up the part number on the list and enter it in the search box. At least 98% of the 1968 3hp parts are the same as the 1967.
Most everything you need to get that motor going is available here at iboats.

 

[lindy46]

Re: 3 hp 67 lightwin advice....

2 motors for $30 - a no-brainer! Spray some PB Blaster in the cylinders and let it soak for a few days with cylinders pointing up. That may inseize the motor. Probably just stuck rings. '52-'68 were all pretty much the same motors. If the powerhead is shot on the one motor, it's an easy job to put the other powerhead on. A great little motor - that's why they didn't change them much for 16 years.

 

[Sea Raider I]

Re: 3 hp 67 lightwin advice....

I went ahead and offered 20 bucks, he took it.. This motor is pretty much rusted tight. Tore it down (with many more pics) and pulled the head. The holes have some rust but no scars(that I can see now). Went and got some PB blaster and she's soaking right now. I've been told to use a torch, thoughts?? I filled up the holes with blaster and plan to try again in the morning. Ill post progress...

 

[Sea Raider I]

Re: 3 hp 67 lightwin advice....

She lives!!! Got the motor turning, put on a new head gasket, installed new spark plugs and she fired right up!! Now, I believe I should rebuild carb as it will not idle without the mixture screw seated. At higher speeds I can adjust it out, but at idle it has to be seated in order to run. Am i thinking along the right track here??

Thanks..

 

[nwcove]

Re: 3 hp 67 lightwin advice....

you got it, go with the carb kit! get needles and seats also.

 

[1946Zephyr]

Re: 3 hp 67 lightwin advice....

Good little engines. You stole them for 20 bucks. Run the mix at 16:1 and they'll outlast you.