Hi guys. I am trying to replace the driver's side valve cover gasket on my '90 f250 351. I have gotten all of the emissions junk out of the way except one thing. I don't know what they are called, but I can't get the metal tubes that go into the top of the exhaust manifold off. Does anybody know how to get these off? There looks to be two nuts, one that threads into the manifold, and one that threads into the other nut. I'm really stuck here, becuase the valve cover won't be able to come out until this part is out of the way.

Thanks guys,
Hunter

 

I don't know crap about 351s except to the extent that they resemble 302s but it sounds like you're describing an EGR tube and fitting. If so soak the living hell out of it with the best penetrant you can find. Many people like PB Blaster but YMMV. Let it sit over night. Take it apart at the fitting. USE TWO WRENCHES. Hold the part of the fitting that screws into the manifold so it cannot rotate and back off the compression nut. It will not come willingly or easily. You must re-assemble with high-temp never-sieze.

 

Crap. That sucks, I was hoping to get this done today. After looking though, I might be able to get the cover off without removing the EGR tubes. I have all of the valve cover bolts removed, but I can't get the d@mn valve cover to come off. I have tried hitting it with a rubber mallet, but I'm afraid that if I hit it any harder I'll dent it. Anybody have any tricks for getting these things off.

Thanks again,
Hunter

 

Well, I got 3 of the 4 EGR tubes off after letting the PB Blaster soak on them for about 30 minutes. The tube that goes to the #8 cylinder won't come off though. I'm gonna let it soak a while longer before I round the nut off. Thanks for the tip StrangeRanger, that PB Blaster is some good stuff.

Hunter

 

Got everything off now, including the valve cover. Thanks StrangeRanger. Hopefully I can get everything back together correctly. I wonder how many vacuum lines I broke while doing this?

Hunter

 

Those aren't EGR tubes. If they run to the individual cylinders, they must be secondary air injection. I had assumed that the 351 did that internally likethe 302. If you got that stuff apart, congratulations. it's usually "self-welded" frtom the exhaust heat

 

Those riggin fraggin vacuum lines . I break one every time I work on my rig. I wish Ford sold a vacuum line replacement kit. They don't even sell the rubber blocks that multiple lines go into.

Sounds like your showing that 351 who's boss... Good work man.