exhaust manifold fit (1 Viewer)

[ukboneman]

I am in the process of rebuilding the F engine on my '73 FJ40. The original exhaust manifold had a frozen/corroded heat riser, do I decided to replace it. I found a nice intake/exhaust manifold set here on MUD. I dry fit them when they arrived and they fit fine. I then sent them off to be sandblasted and ceramic coated in the case of the exhaust manifold. Just went to fit them and this is what I found: any ideas? can I just grind that corner of the EM that so that it will fit over the stud? Makes me think that somehow it warped during blasting? seems hard to believe but it definitely fit. I did replace the studs.

 

[erics]

on later models I believe there are a couple thick gaskets sandwiching a deflector plate deal in between the two manifolds - something like that would "raise" the intake and largely fix your alignment issue.

 

[OPMACHINE]

looks like you are missing the gaskets and heat riser/block off plate, that go between the two manifolds.

 

[ukboneman]

yeah, I have not installed those yet because I am trying to figure out this issue. I don't think it will effect how the mounting sites line up on the head, but I am going to try and see.

 

[Steamer]

When I got my 74 the exhaust manifold was warped just like that and maybe slightly worse. It was prone to exhaust leaks at the bottom of the 1 & 6 ports since there is not much contact surface there to begin with. I made my own stainless block off plate, but it was too thick, where it the brought the ends into alignment but resulted in the center ones being staggered. So, I ditched the plate and came up with a thicker gasket that evened up the stagger between the outer and center mounting points. I had to split washers in half so they would fit in the recess with the stagger.

I got it to work but it was finicky. Luckily at the time (20 years ago), I found out that new manifolds were still available and so I bought one. Wish I had bought 2.

 

[KY Longhunter]

It’s been recommended that you mount intake/exhaust manifold to head finger tight BEFORE tightening the intake and exhaust manifolds together. And the block off plate.

I failed to do this and now regret it.

 

[firemanj92]

I am in the process of rebuilding the F engine on my '73 FJ40. The original exhaust manifold had a frozen/corroded heat riser, do I decided to replace it. I found a nice intake/exhaust manifold set here on MUD. I dry fit them when they arrived and they fit fine. I then sent them off to be sandblasted and ceramic coated in the case of the exhaust manifold. Just went to fit them and this is what I found: any ideas? can I just grind that corner of the EM that so that it will fit over the stud? Makes me think that somehow it warped during blasting? seems hard to believe but it definitely fit. I did replace the studs.

View attachment 2731367

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looks like you are missing the gaskets and heat riser/block off plate, that go between the two manifolds.

The gaskets will help align the holes better. I had mine machined, they assembled them with the gaskets then machined 'em. So assemble them on a flat surface if possible for better surface alignment.

 

[Spike Strip]

Gaskets !

 

[ryanwk628]

Gasket will push the manifold down bringing that half of the circle more into alignment. You can get a heat riser block off plate from @cruiseroutfit .

 

[cruiseroutfit]

Gasket will push the manifold down bringing that half of the circle more into alignment. You can get a heat riser block off plate from @cruiseroutfit .

Yup

Heat Riser Block Off Plates for your F/2F

Suffering from a cracked intake manifold on your F or 2F engine? Many F/2F equipped Land Cruisers suffer from a cracked intake causing a major vacuum leak and poor running conditions. It's possible to have your intake professionally tig-weld repaired but we have a much cheaper alternative...

forum.ih8mud.com

 

[ukboneman]

You guys are just too freaken' smart. I put in the heat riser gasket and just finger tightened the bolts so that the manifolds could "settle" flat. I did use one of the expensive SOR thick gaskets for the manifolds. I did have to grind away less than 1mm of exhaust manifold at that stud. Everything did fit much better with the gasket intact. I then rebuilt the heat riser spring mechanism. I live in Maine and would like to have a functioning heat riser. Isn't the block off plate used if there is a crack? Now, if I could figure out how to rotate these photos so they aren't 90 deg off.

 

[ukboneman]

Thanks everyone for your help. I could never do this project without MUD. BTW, I rebuilt the transmission, transfer case, knuckles and rear axle using Cruiser Outfitter kits. The kits were all top notch.