captinjohn

Here is the question. Do any of the 4 cycle engine brands in use have valve seat inserts that can be replaced? I am working on a 4 cycle engine that has 4 cylinders. The valve head dia would need to be maximum of .437. The stem dia about .125 & length around 1 3/16 to 1 1/2 long. Sure would like to locate the valves anyway. The seats is only needs for repair & not many would be needed. Thanks in advance, john

av8tor1977

My Feedback: (6)

Hey John. Look up in your engine resources about making valves. You should be able to make them with your lathe. As far as I know, most model engines do not have replaceable hard seats.

AV8TOR

captinjohn

AV8TOR, Thanks for the reply. I was most interested in replaceable valve seats, to repair one valve seat. I got that one done now. I should have posted this in the engine conversion thread. It is sad to see not much posted there like before. I cannot understand why. It may have to do with all the cheap china made gas engines made now. Best Regards, john

av8tor1977

My Feedback: (6)

Yeah, that bums me out about the Conversions Forum too. And I think it is because of the reason you stated.

I don't know if it will help you or not, but I just measured the valves from a Stihl 65cc Four Mix. The head is .800", the stem is 1.36", and the length is 1.760".

AV8TOR

captinjohn

Thanks AV8TOR, Those are a tad big for the engine I am doing now. But that data is very good to have for the "next" engine project. I wish some of the guys that run Saito OS Max or any 4 cycle engine owner would post the valve sizes. Best Regards, John

Truckracer

My Feedback: (19)

I have worked on a number of glo 4 strokes and most had "cast in place" seats that appeared to be bronze. I have never read where any of them were replaceable or available other than with the head casting. What is your head material? Iron or aluminum? If iron, I would think the head material itself would be adequate for a valve seat considering the limited amount of runs a model engine would experience.

As far as valves go, there should be something available out there that can be adapted to your use. You might contact someone like Clarance Lee as he might have some suggestions for your project.

captinjohn

Thanks very much. I will try to Pm Clarance Lee.

Truckracer

My Feedback: (19)

Probably the best way to contact him would be through Model Airplane News ... by traditional mail or phone. I have never seen him on any of the common forums.

C.F. Lee Mfg. Co.
10112 Woodward Ave.
Sunland, CA 91040

818-352-3766

He has addressed strange and homebuilt engines in his various columns over the years so maybe there is a change he could send you in a positive direction.

Gizmo-RCU

My Feedback: (27)

I had Mr. Lee repair an engine, had no problem making contact by phone.

captinjohn

I called & talked to his wife. She asked him, but he did not have any notes on valve sizes. She says he mostly repairs stripped out glow plug hole threads & repairs other threaded parts. .......

KenLambert

My Feedback: (107)

I have a manual for an American made 4 stroke glow engine I will check the valve setup , I know it has 4 , dohc would be known as the predator 120