Farm Equipment - D 15 valve seals

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D 15 valve seals

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Topic: D 15 valve seals

Posted By: AaronH
Subject: D 15 valve seals
Date Posted: 19 Jun 2010 at 7:41am

Series one, not very familiar with this engine. It will puff some oil smoke when I start it and the the gauge starts showing oil pressure, then will will slowly go away. Does this engine have some sort of valve seal? I am just thinking if I replace them this little problem will go away. It does not smoke all the time so I do not think its the rings. Any other ideas before I pull the valve cover?

Replies:

Posted By: CTuckerNWIL
Date Posted: 19 Jun 2010 at 9:10am

I'm kinda thinking there probably aren't any valve seals in that engine . None were used in earlier engines. It sounds to me like the guides might be wore. A valve guide seal will not effect your oil pressure anyway. What oil are you using. I use straight 30w for tractors in the summer, if I had a low pressure situation I might try some heavier oil as long as it's warm. How far down does the pressure go? These old engines never had or needed a lot of pressure. If you have insufficient oil pressure with 30w oil, I would guess the cam, rod and main bearings are probably a little on the loose side. Charlie

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Posted By: JimD
Date Posted: 19 Jun 2010 at 9:33am

Charley, I think he means the smoke goes away, not the oil pressure.

Could be a valvetrain issue. No seals, just guides on your engine. Rebuilding the head is easy, and kits aren't very expensive.

But I'm, not sure it's valves. I think you may have a oil ring on the piston sticking. We have had them do that and rebuilt the head with the problem still there. I agree, go with a little heavier oil and see if it wil buy you some time beofre a rebuild. If not, you need to at least re-ring the engine, but be aware, that often you can rebuild with new parts for not much more than rings and gaskets.

JImD

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Posted By: AaronH
Date Posted: 19 Jun 2010 at 12:40pm

The engine holds a solid 20 lbs of pressure, dont smoke right away, just when there is enough oil pressure to be oiling the top of the engine, but it does go away. I am using 10 w 40 with a quart a lucas oil conditioner. It runs very good and has plenty of power, but the valve guide issue is very possible.

Posted By: CTuckerNWIL
Date Posted: 19 Jun 2010 at 12:56pm

If the only problem you have is the little puff of smoke, I wouldn't worry about it too much. My 38 B smokes like a steam engine on start up, but I only run it about a hour each week to mow and it can smoke a long time before I get projects caught up to worry about it.

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Lena 1935 WC12xxx, Willie 1951 CA6xx Dad bought new, 1954WD45 PS, 1960 D17 NF

Posted By: Brian Jasper co. Ia
Date Posted: 19 Jun 2010 at 8:44pm

So if I understand you correctly, you say after the oil pressure builds, then it starts smoking at idle? Quite likely the guides are worn, but you might also want to look to make sure it isn't pooling oil on the head where it could over run the guides and be sucked down them. Had a 460 Ford do that once. Smoked a fair amount on 1 side at idle. (dual exhaust) Rear drain back hole in one head was plugged with a piece of umbrella valve seal. Knocked the piece out and it stopped smoking at idle.

My 60 Oliver (has very similar design to B,C,CA engines) that has all new valves and guides on a no expense spared overhaul gives 1 big puff of smoke on a cold start. No smoke running. It has no valve stem seals and never did. My CA will give a puff of smoke on a cold start too. It also got new valves and guides on a complete overhaul.

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