Makita / Dolmar 7900 Piston and Cylinder Install w/ PICS!!

[tjbier]

... The hard part of this install is over.

Yep definitely a keeper!! I am waiting for the HD kit yet , but I painted the stock bonnet and filter cover from grey to black yesterday with a rattle can and baked it in the oven for 25 min @ 175deg.

Well done and appreciate the pictures!

 

[buzz sawyer]

great thread.

i noticed those pistons have beefy port windows. i bet they could go through a pretty good weight loss program

My thoughts exactly. That intake port looks considerably larger on the 7900 jug too.

Great post- rep sent!

Next-----VIDEO!!!!

 

[KMB]

Yep definitely a keeper!! I am waiting for the HD kit yet , but I painted the stock bonnet and filter cover from grey to black yesterday with a rattle can and baked it in the oven for 25 min @ 175deg.

Well done and appreciate the pictures!

Got any pics of that paint job?

Kevin

 

[04ultra]

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Why didn't you use the 965.531.160 Metal base gasket ????





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[tjbier]

You bet! Might not be as nice as OEM but hey it works for me.

 

[stock50s]

In your initial pics it looks like the mating surface for the muffler isn't machined on the 79cc cylinder. Seems odd if so, you want a good seal there. I figured my eyes deceived me.

Jack

It looked like the cylinder was only machined on that one AV mounting hole. The the exhaust surface was flat and I could barely see machine marks but did not look machined like the AV mount. The spark plug hole and mating surface both, and the decomp hole all looked dull like the rest of the cylinder. Maybe they machine the critical spots and the dunk the cylinder in something to prohibit corrosion? I know it is not, but it almost looks galvanized. I realize that would not explain the AV mount unless a correction had to be made later on. Anyone have any ideas as to why the cylinder would be that way?

 

[stock50s]

Why didn't you use the 965.531.160 Metal base gasket ????





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That is the one that was included with the p/c. I also was not aware that a metal one existed. Is there a difference in thinkness between the two?

 

[04ultra]

That is the one that was included with the p/c. I also was not aware that a metal one existed. Is there a difference in thinkness between the two?

Metal one is the updated one ............






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[grandpatractor]

That is the one that was included with the p/c. I also was not aware that a metal one existed. Is there a difference in thinkness between the two?

I am not sure if there is a thickness difference, but the metal one is the newer updated part and I believe it to be more robust!

 

[stock50s]

Metal one is the updated one ............






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Bummer!! Was there a problem with the other ones blowing out? I would hate to have it let go and loose a p/c over a $2 gasket. I may just have to pull it back apart and replace the gasket now that you have me worried.

 

[04ultra]

Bummer!! Was there a problem with the other ones blowing out? I would hate to have it let go and loose a p/c over a $2 gasket. I may just have to pull it back apart and replace the gasket now that you have me worried.

From what Im told the metal holds up a lot better........... The metal gasket has been used for a couple years now......








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[grandpatractor]

Bummer!! Was there a problem with the other ones blowing out? I would hate to have it let go and loose a p/c over a $2 gasket. I may just have to pull it back apart and replace the gasket now that you have me worried.

I don't know if I would tear it back apart, but I would check the base screws occasionally and make sure they stay tight!

 

[nmurph]

where did you get that cylinder? i have done two of these conversions and neither of mine looked like yours.

 

[rms61moparman]

Bummer!! Was there a problem with the other ones blowing out? I would hate to have it let go and loose a p/c over a $2 gasket. I may just have to pull it back apart and replace the gasket now that you have me worried.

Don't worry about it.
My base gasket is a thin bead of permatex#2.


Mike

 

[KMB]

You bet! Might not be as nice as OEM but hey it works for me.

Looks fine...and you saved yourself a few bucks.

Kevin

 

[wendell]

Great job!! I tried to rep ya but it said i have to spread it around.

 

[CHEVYTOWN13]

Why didn't you use the 965.531.160 Metal base gasket ????





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I agree. The metal gasket is tops. It even snaps into place and is handy when installing the jug. The best part about it is it lowers your squish.

 

[stock50s]

I agree. The metal gasket is tops. It even snaps into place and is handy when installing the jug. The best part about it is it lowers your squish.

Well guys I think I am going get the metal gasket. I can't imagine that Dolmar would replace the gasket if the old one was not prone to problems. I purchased the p/c from a site sponsor. If the new metal gasket has been out for a few years, it is a little disappointing that the old style was included. So no one has received a p/c that looked like the one I received?

 

[04ultra]

Well guys I think I am going get the metal gasket. I can't imagine that Dolmar would replace the gasket if the old one was not prone to problems. I purchased the p/c from a site sponsor. If the new metal gasket has been out for a few years, it is a little disappointing that the old style was included. So no one has received a p/c that looked like the one I received?

The place that shipped you it is a Dolmar dealer???




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[stock50s]

The place that shipped you it is a Dolmar dealer???

Yes they are. I would think that if a new part comes out because of an issue Dolmar should take back the old inventory as to prevent more problems. I think I will give the sponsor a call on Monday and see what they have to say. I don't want to make a mountain over a mole hill but at the same time this may be beneficial to others that do this conversion. The metal gasket is only $2 and I gladly would have payed that had I known it was the updated one.