2F Manifold Woes - need advise please

[berntd]

Hello,

Long story short:

I had to replace the old extracors as they were done for and bought a new set, that one is the ouside chassis type as per orginal exhaust run.

That worked for 2 months and then started leaking at cyoinder 4/5 and eventually the whole gasket was shot.

I tried again, same story.

The head surface was re-faced. (I overhauled the head)

I then bought a used original manifold and with great difficulty fitted that. It had been re-surfaced before me but the Alu intake bits / ears were much thinner than the cast exhaust bits so i had to make special step washers etc etc.
This time I had one of those red asbetos type gasktes - not the metal ones.

2 weeks later, it started leaking again at cylinder 4,5. I left it as it was little.

Then recenly, 2 months later I got a rough idle and eventually (!)found that the motor is sucking air at around cylinder 4 throuygh the manifold gasket.

This is an endless problem !!

New manifolds and parts like the insulator gaskets seem to be unavailable from local Toyota.

I could make 2 manifolds into 1 that will not need step washers but not without those gaskets. Are they available somewhere?



How else can I cure this problem for good?



Kind regards
Bernt

 

[tlc_4play]

I used 2 x manifold gaskets

 

[grant5127]

New manifolds and parts like the insulator gaskets seem to be unavailable from local Toyota.

Part #17100-61084 sold as a single piece unit, about 800$.... you'll need a few other parts to make it work, but no biggie....

Better off using a good intake and a header with double gaskets.....

 

[Southeast Overland]

If your leak keeps reappearing at 4/5 where it mates to the block try either an OEM gasket with a bunch of copper coat sealant OR better yet a Remflex gasket.

 

[LAMBCRUSHER]

Yeah, brand new is a for sure thing. If you had a decent intake/exhaust combo, all bolted together, take it to a machinist and have it milled for flatness, AND spot face the bolt flanges. If your alum/ cast iron bits are at two different thicknesses, warpping is only a matter of time. Spotfacing mills the bolt flange faces to the exact same thicknesses. I've also given up on one piece exhaust manifolds. The later 77+ manifolds have a three piece design to give a bit of flex and cut down on cracking and warpping.

 

[berntd]

Yeah, brand new is a for sure thing. If you had a decent intake/exhaust combo, all bolted together, take it to a machinist and have it milled for flatness, AND spot face the bolt flanges. If your alum/ cast iron bits are at two different thicknesses, warpping is only a matter of time. Spotfacing mills the bolt flange faces to the exact same thicknesses. I've also given up on one piece exhaust manifolds. The later 77+ manifolds have a three piece design to give a bit of flex and cut down on cracking and warpping.

NOT AVAILABLE HERE = NLA from Toyota :-(

How about the gaskets that fit between the 2 manifolds on the hotbox ?

Also NLA from Toyota here.

Regards
Bernt

 

[LAMBCRUSHER]

Right, you're from down under. I can get those exhaust to intake insulator gaskets from napa- have a couple on my workbench! Have you thought about MAF or Specter? They are both So.California companies that are on line and have the parts you need. I know that the factory insulator is still available from Toyota here in the states for about 50 bux- I just got one. Specter has an aftermarket insulator block off plate which requires trimming or removal of the heat riser flap inside the exhaust manifold for about 35 bux. The remflex gasket is another aftermarket gasket that has a good reputation for sealing pesky manifold leaks, and I have also heard of the doubling up on gaskets working too.

 

[Roryfj4062]

I used 2 x manifold gaskets

as did I, with copper goo in between, no leaks in over a year, using an unknown header and new to me 2f, neither surfaces machined.

 

[berntd]

Right, you're from down under. I can get those exhaust to intake insulator gaskets from napa- have a couple on my workbench! Have you thought about MAF or Specter? They are both So.California companies that are on line and have the parts you need. I know that the factory insulator is still available from Toyota here in the states for about 50 bux- I just got one. Specter has an aftermarket insulator block off plate which requires trimming or removal of the heat riser flap inside the exhaust manifold for about 35 bux. The remflex gasket is another aftermarket gasket that has a good reputation for sealing pesky manifold leaks, and I have also heard of the doubling up on gaskets working too.

Hi I can get the insulator from Toyota as well. it is a sheet metal plate - sort of.

I cannot get the 2 gaskets though. How thick are these? Maybe I can make them from csomething?

Kind regards
Bernt

 

[grant5127]

Insulator......

As far as the gaskets goes.... you don't have access to Felpro products??............

 

[berntd]

Maybe, depends as nobody here stocks anything really but I can try.

which of those shown is the part number for the Felpro gasket for this?

Regards
Bernt

 

[Fast Eddy]

the factory insulator is still available from Toyota here in the states for about 50 bux- I just got one. Specter has an aftermarket insulator block off plate which requires trimming or removal of the heat riser flap inside the exhaust manifold for about 35 bux.

The stock insulator can cause the aluminum intake to crack. The block off plate is designed to help prevent this problem. I have one. This is the first I've heard about removing the heat riser flap.

It would be difficult to get it out of there if you have a CA Thermal Reactor manifold (which may be rare enough, I suppose). You'd need a 10" long tip for your cut-off torch to get down into the manifold to cut the shaft. The flap/shaft is not serviceable. The shaft was inserted and the flap is tack-welded to it during manufacturing. I considered drilling the shaft out of both sides, but I fixed up the spring assembly and got it working instead.

 

[grant5127]

Maybe, depends as nobody here stocks anything really but I can try.

which of those shown is the part number for the Felpro gasket for this?

Regards
Bernt

Felpro # MS22813.....
Comes with 2 insulator sandwich gaskets and one int.~exh. gasket........

 

[Centermass]

Iron_giant can get you a remflex gasket. I had he same problem tried the others but only remflex fixed my problem. Also you can have the intake and exhaust machined as one unit they weld on the ends and now you have flat manifols and you just grind the tack welds off holding the ends on before mounting. I also had to mix and match intake and exhaust manifolds and this was also a solution along with remflex from Iron_giant. Good luck

 

[berntd]

Hello all and thanks for the help.
Took the manifold off this mornign and found a real mess.
The gasket (about 6 weeks old) seems to have shrunk and there is a hole chumk of it just not there.

I could not really see much warpage so I fitted another new metal gasket with copper silikon. Let's see how lonh that lasts.

I also noticed that the flap in the manifold is broken off its shaft on one side. I also noticed that the shaft will need new bushes fitted as it leaks there badly and it jas tons of radial play. I now wired the flap into the hot position (we don't need that here in Aussie anyway) until I get the right gaskets so I can diassemble it and re-bush/repair it.

Kind regards
Bernt

 

[grant5127]

I also noticed that the flap in the manifold is broken off its shaft on one side. I also noticed that the shaft will need new bushes fitted as it leaks there badly and it jas tons of radial play. I now wired the flap into the hot position (we don't need that here in Aussie anyway) until I get the right gaskets so I can diassemble it and re-bush/repair it.

Hot position???
You don't want wired in the hot position, that will allow extreme heat on the underside of the intake and cause it to crack, if that happens a huge vacuum leak will haunt you....

If the heat riser is not needed, remove it along with the shaft and just weld up both end holes in the manifold.....

That gasket you have there was no good to start with, just a generic header gasket..........

 

[berntd]

Hot position???
You don't want wired in the hot position, that will allow extreme heat on the underside of the intake and cause it to crack, if that happens a huge vacuum leak will haunt you....

.

Thankls for that. I have it correct. It is the rterminology that is the problem.

Hot psoition means engine is hot and cold positon means engine cold.



Yea, what a crappy gasket and they assured me when I bought it that it is much beter than the new style etal ones - Yea right!!


Kind regards
Bernt

 

[Centermass]

Berntd
Is the copper silicone rated to handle the amount of heat that is generated from the exhaust. I put mine on dry no sloppy mess. check out REMFLEX Exhaust Gaskets: Home Page there made of graphite and good for 3,000 degrees F.

 

[Fuzzy Logic]

Does the remflex gasket come with the 2 sandwich gaskets as well?

 

[Centermass]

I dont know what gasket that is. Is it the one between the intake and exhaust manifolds. the remflex is 1/8 inch thick and can be crushed to 1/16 inch thick and you only torque it to about 16ft pounds. Torque it down one time that is it. Here is what the have for the f-2f motor Remflex exhaust gaskets (header - manifold - gasket) - OnLine Catalog it says it is a 4 paice set. I only used the exhaust gasket.