JD 50 manifold bolts

[tpfixit]

Recently purchased a JD 50 and need to replace the exhaust and intake manifolds. I am looking for tips on how to get the exhaust bolts loose without breaking them off in the head. Was going to use a torch and heat them but don't know how much good this will do since the threads are so far from the head of the bolt. Also, you can't really get penetrating oil down to the threads. Any suggestions would be greatly appreciated. Also, if anyone knows of a good place to get replacement manifolds please let me know. Thanks.

 

[JMS/.MN]

Cut the nuts off of the bolt, remove the manifold. Heat the head by the bolt, apply candle wax as it cools. Rap the end of the bolt with a hammer. Stubborn bolts may need a second heat/wax. Never failed me yet.

 

[PJH]

I agree with JMS/.MN

In addition, I recommend that you go slow and easy as you try to turn the bolts. If you can get a tiny bit of movement, then keep working it back and forth and you'll gradually get more movement. I recently removed the manifold on my 50. I used a weld grinder to cut the bolt heads off.

This site sells manifolds.
YT manifold for sale

 

[matthies]

If the hood is off it goes a lot better, otherwise place a small ball peen hammer on the heads and take a larger hammer and give the small hammer a few good wacks then try the bolts, wack again and try the bolts again till loose. Patience goes a long way. Might as well try the manifolds from this site, Steiner's manifolds leak around the heat valve, A&I was better but not much. chris

 

[PJH]

"Steiner's manifolds leak around the heat valve"

OUCH! Bad news! I have a new manifold from Steiner ready to put on my 50. I wonder if I could use valve lapping compound to clean up the fit?

 

[matthies]

You will need more than lapping compound, at least on the one they sent me. I complained so they paid to return it and look at it, that took three months and a lot of calls. They tried to turn it on the lathe but still no good. Finally they took it back and refunded my money. Their tech Dennis said they all leak, some guys complain some don't. Hopefully you have a good one. Bought one from them a year earlier and no problems but can tell it was a different casting. Just slide the valve up in the manifold and see if it rocks in the housing and also check the gap around the top of the valve/manifold. chris

 

[Mike M]

I just figured all of the overseas repops are coming from the same source ? Don't know for sure though.

 

[PJH]

I checked the fit on my new manifold, and it appears to be a good one.