Engine Trouble (1 Viewer)

[Pighead]

The Remflex gasket worked well for me after two failed OEM gaskets

The Remflex gasket might have worked better for me if I'd prepped the header/intake mating better, and it should work fine with stock manifolds. But Remflex instructions say DO NOT OVERTORQUE, and they specify lighter than stock torque specs. Mine still leaked at their specs, so I torqued more...

 

[OhioFJ]

I found this broken vacuum switch laying inside part of the air cleaner (first picture). Any idea where it came from or a complete part number?

I can’t find the corresponding broken half.

 

[Pin_Head]

The Remflex gasket might have worked better for me if I'd prepped the header/intake mating better, and it should work fine with stock manifolds. But Remflex instructions say DO NOT OVERTORQUE, and they specify lighter than stock torque specs. Mine still leaked at their specs, so I torqued more...

Me too. Their torque specs are way low. I torqued them down good and hard. I don’t remember ever seeing the Toyota torque specs for the manifold.

The thing about the Remflex is that it expands in the heat, so it is very tolerant of warped, mismatched parts.

 

[pithicus]

Toyota Part No.:90925-05075
VALVE, BIMETAL VACUUM SWITCHING
Could be it.
I think it's a egr vacuum delay valve

Edit I think the number for a 40/55 etc is 90925-05017

more details here 90925-05017 Valve, Bimetal Vacuum Switching, No.1, Toyota

 

[Pighead]

I’m assuming the manifold gasket is leaking, and it probably is l but I can’t confirm. The edge of the gasket that I can see looks like crap. Before I delve into it I’m going to replace all my vacuum lines and rebuild the carb.

As much of a pain as it is to get the carb off and on, it seems like a smaller job than removing all the stuff I need to remove in order to get to the manifold on this smogged engine.

What I might do, instead of diving right into replacing manifolds gasket, is while the carb is off, start soaking (spraying liberally) your manifold nuts with a PB blaster (or better) for hours or days. Then, sorta gently, see if you can back off each nut, one at a time. If you can get them loose and unthreading, re-torque them tight to factory specs (which I don't recall, but are in the FAQs) and maybe, if your nuts are tolerating that torque, just a hair tighter.
These nuts do need a re-torque or two when a new gasket is installed, maybe they have worked loose over time. Might also provide some insight into how many studs/nuts you'll want to have on hand when you finally do decide to replace that gasket. I take no responsibility for any breakage or strippage which may occur if you try doing anything that I might do...

 

[OhioFJ]

I like this idea - I think the gasket will have to be replaced eventually and soaking / testing will be required at that time. might as well see what I'm dealing with now. Thanks for the advice - much appreciated.

 

[OhioFJ]

Toyota Part No.:90925-05075
VALVE, BIMETAL VACUUM SWITCHING
Could be it.
I think it's a egr vacuum delay valve

Edit I think the number for a 40/55 etc is 90925-05017

more details here 90925-05017 Valve, Bimetal Vacuum Switching, No.1, Toyota

Thank you - so strange - the one in the thermostat housing is intact. the fragment that I found must have been dropped in there during a prior service. I can't seem to find a second one.

 

[OhioFJ]

Glad to report major improvements.

All it took was:
- Rebuild carb
- Change plugs and wires
- Change all vacuum lines
- Oil and filter change
- Set timing
- Tuned carb


I think the major culprit was a gummed up carb; there were parts in there that were cemented together.

Did the carb tuning method per the FSM and was able to achieve idle at 650. I was thrown at first because the fast idle screw was in and preventing the idle speed screw from doing its thing. Once I backed that up I was good to go.

I've read (I think) about checking timing again after carb tuning, and going back and forth between tuning the carb and timing, but haven't had the chance. Is that correct?

I'm just happy the thing is running! Thanks again to everyone who has taken the time to respond to my questions.

 

[Pin_Head]

Congratulations. Sometimes it is the carb and they aren’t that hard to rebuild, are they?

 

[OhioFJ]

Well, thanks to you it was a lot easier for a monkey like me.

It did give me a great appreciation for the complexity of this component. A bit of genius engineering really.