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WheelHorse520H

Onan P220 surging/hunting at operate

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WheelHorse520H
9 hours ago, tom2p said:


no worries - muffler is fine ... paint on the muffler is not too bad ... 
 

Yeah, but I am going to repaint it to keep it from rusting and to make it look nice.

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Tuneup

My compliments, sir. I will clean it as best I can and then carefully scrape and polish but won't spend more than an hour on one of these heads. By the way, that muffler is in top condition.

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WheelHorse520H
2 minutes ago, Tuneup said:

My compliments, sir. I will clean it as best I can and then carefully scrape and polish but won't spend more than an hour on one of these heads. By the way, that muffler is in top condition.

Thank you, I want it to run and look excellent.

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tom2p
3 hours ago, WheelHorse520H said:

Yeah, but I am going to repaint it to keep it from rusting and to make it look nice.


I was referring to the muffler on my 416  

 

I spray the muffler with WD-40 on occasion 


but if you insist on painting my muffler after you complete decarbon and valve adjustment - go for it 

 

lol

 

Edited by tom2p
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WheelHorse520H

Good news:

The company that I bought the paint from said they would send along money for me to sandblast and repaint the exhaust!:lol::woohoo:

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Jeff-C175
1 hour ago, WheelHorse520H said:

Good news:

The company that I bought the paint from said they would send along money for me to sandblast and repaint the exhaust!:lol::woohoo:

 

WOW!  That's amazing!

 

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Horse Newbie
4 hours ago, Jeff-C175 said:

 

WOW!  That's amazing!

 

I thought he was kidding...

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WheelHorse520H
10 hours ago, Horse Newbie said:

I thought he was kidding...

Nope they asked for the barcode number the batch number and a few other things and said they send along the $.

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WheelHorse520H

Did some sandblasting today once the rain cleared… well it was more of a drizzle than anything. For some reason some of the primer didn’t come off or the metal has been discolored which is why it has the weird pattern. Now I am priming the exhaust again.

52BF5526-5A65-49B2-B8E5-D60C4691C1B4.jpeg

1DC8382F-1D90-4CC0-8764-7CBB8FCA0A75.jpeg

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WheelHorse520H

I made the heads as true as I could, the dark areas are little pits. I think they are good to go back on, I got my gaskets a few minutes ago. Is there anything I should do to clean the mating surface on the engine block?

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Also, the valve covers rusted a little, should I worry about that?

3F3283E7-C2B6-4323-A84B-D767662345EF.jpeg

Edited by WheelHorse520H
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WheelHorse520H

Glad I went through the gaskets, the one between the carb and intake is too big. Suggestions?

1698AFEB-D3E6-44A5-BC65-DD04AC26C4A4.jpeg

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Handy Don

Isn't there a spacer that raises the carb up off the manifold? That gasket looks like the one between the carb and the spacer, not the spacer and the manifold.

 

The external rust on the valve covers isn't serious, but you should clean the gasket-facing surfaces. Also, you have the manual so follow the torque specs carefully when reassembling--the valve cover nuts are little more than finger tight!

Edited by Handy Don
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Jeff-C175
1 hour ago, WheelHorse520H said:

the valve covers rusted a little, should I worry about that

 

That won't affect the performance, only the appearance, so it's up to you how good you want it to look!

 

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WheelHorse520H
51 minutes ago, Handy Don said:

 

Isn't there a spacer that raises the carb up off the manifold? That gasket looks like the one between the carb and the spacer, not the spacer and the manifold.

 

Yes, that would be it. I did not see it at first.

 

48 minutes ago, Jeff-C175 said:

 

That won't affect the performance, only the appearance, so it's up to you how good you want it to look!

 

Honestly they’re so far down you barely see them.

 

Is it okay to put the cylinder heads back on even though they are not perfect?

Edited by WheelHorse520H
Made a mistake.

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lynnmor

Obviously that gasket is totally wrong, the correct gasket will have a hole that is larger than necessary, but the bolt holes need to be correct.  I always clean and paint the valve covers because water can puddle in the depressions and cause rust.  The block has burrs raised up around the bolt holes, I use a countersink and cut them to just over the bolt diameter.  I then run a tap in those holes to clean the threads so that the bolts can be properly torqued.  I use one drop of oil on the bolt threads per Onan manual.  The same countersinking and tapping is also done on all the intake and exhaust holes as well.  Do not cheat on the torque specification, they have a tolerance and you should use the average, it is easy to strip the threads with just a little too much.

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WheelHorse520H
13 minutes ago, lynnmor said:

Obviously that gasket is totally wrong, the correct gasket will have a hole that is larger than necessary, but the bolt holes need to be correct.

I believe it is the one in between the carb and the spacer but I did not take it apart there.

 

15 minutes ago, lynnmor said:

I always clean and paint the valve covers because water can puddle in the depressions and cause rust.

I assume you only paint the outside because the inside has oil circulating.

 

17 minutes ago, lynnmor said:

The block has burrs raised up around the bolt holes, I use a countersink and cut them to just over the bolt diameter.  I then run a tap in those holes to clean the threads so that the bolts can be properly torqued.  I use one drop of oil on the bolt threads per Onan manual.  The same countersinking and tapping is also done on all the intake and exhaust holes as well.

To be clear (mostly so I don’t make a mistake) you do this process for the intake, exhaust, valve covers, and the cylinder heads. Correct?

 

Please see post 135 about the gasket surfaces on the engine block and the cylinder heads.

 

Thanks,

Andrew

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lynnmor
8 hours ago, WheelHorse520H said:

I believe it is the one in between the carb and the spacer but I did not take it apart there.

 

I assume you only paint the outside because the inside has oil circulating.

 

To be clear (mostly so I don’t make a mistake) you do this process for the intake, exhaust, valve covers, and the cylinder heads. Correct?

 

Please see post 135 about the gasket surfaces on the engine block and the cylinder heads.

 

Thanks,

Andrew

 

Do you have two pairs of bolts holding the carburetor on?????

 

Of course there is no need to paint the inside.

 

Cleaning tapped holes is good practice.

 

I did see your post and saw the burrs.

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WheelHorse520H
1 hour ago, lynnmor said:

Do you have two pairs of bolts holding the carburetor on?????

Yes, photos to follow later today.

 

1 hour ago, lynnmor said:

Of course there is no need to paint the inside.

Just had to be sure.:rolleyes:

 

1 hour ago, lynnmor said:

Cleaning tapped holes is good practice.

I am not sure if I have a tap(s) the right size, what else can I do if I don’t?

 

1 hour ago, lynnmor said:

I did see your post and saw the burrs.

And you think they are okay to put on? Also do I need to clean the block or is that okay too?

Thanks for all the help,

Andrew

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WheelHorse520H
10 hours ago, lynnmor said:

I use one drop of oil on the bolt threads per Onan manual.

What page?

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lynnmor
1 hour ago, WheelHorse520H said:

What page?

 

Page 4-1 under the heading "Assembly Torques" in the first paragraph.

 

I hesitate to recommend this, but I use a good quality flat file to dress the block surface.  Without the proper skills, damage can result.

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WheelHorse520H
4 minutes ago, lynnmor said:

in the first paragraph.

Ahh, thank you.

 

5 minutes ago, lynnmor said:

I hesitate to recommend this, but I use a good quality flat file to dress the block surface.  Without the proper skills, damage can result.

I can tell you right now, I do not have the skills for that, is there anything else I can do?

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lynnmor
11 minutes ago, WheelHorse520H said:

 

I can tell you right now, I do not have the skills for that, is there anything else I can do?

 

Use some fine steel wool and remove much of the dark spots.

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WheelHorse520H
2 hours ago, lynnmor said:

 

Use some fine steel wool and remove much of the dark spots.

Done. There are a few little spots left but I think it’s good. Paint on the valve covers is drying, installing those in 1 hour. I will try to separate the spacer on the carb so you can see what @Handy Don was talking about.

903247B2-4289-4BCF-B089-7483B38D8E47.jpeg

77648AFB-6521-4A52-A886-2BA16239B966.jpeg

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Handy Don

Unless you suspect an issue in the carb/spacer connection, I see no reason to separate them. When I overhauled my P218, I didn't disturb that connection!

 

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WheelHorse520H
Just now, Handy Don said:

Unless you suspect an issue in the carb/spacer connection, I see no reason to separate them. When I overhauled my P218, I didn't disturb that connection!

 

I figure since I have the gasket for it why not? Also it looked like it might have torn a little. Couldn’t tell though.

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