1FZ-FE Intake Manifold (1 Viewer)

[HCP2311]

Can anyone shed some light on the dimensions of these bolts and nuts? I assume the nuts are the same size but the two sets of bolts are clearly different. 93 FZJ80 with the 1FZ-FE engine. Already spoke with Toyota about it and the bolts are discontinued and no sizes are recorded for them. And if anyone knows the torque spec for these that would be great to. I am missing the two long bolts and the manifold is currently leaking coolant into the cylinders. Thanks in advance.

 

[CharlieS]

There is no coolant in the upper plenum itself.

Guessing that you have a leak in your throttle body (heating circuit) if it is leaking from that area into cylinders. Seems very odd.

I don't have the nut and bolt specs, but they're nothing special.

I torque mine to "gutentite", but I'm sure the FSM has specs.

Possibly these:
90105-08286
90179-08040
91511-60825

 

[HCP2311]

There is no coolant in the upper plenum itself.

Guessing that you have a leak in your throttle body (heating circuit) if it is leaking from that area into cylinders. Seems very odd.

I don't have the nut and bolt specs, but they're nothing special.

I torque mine to "gutentite", but I'm sure the FSM has specs.

Well I kinda thought it was odd that channels were running through that part of the manifold, but two different people insisted that was true and I couldn't say for sure that I remembered NOT seeing any channels. That entire area has been butchered and Frankensteined together by the previous owner in an attempt to delete the EGR system. I'll see if I can find the diagram for the throttle body heating circuit and troubleshoot from there. I've been wondering if it wouldn't just be wise to replace the throttle body and EGR with a complete system from a junkyard. I'm working backwards from a pile of parts and missing pieces make it just that much more complicated.

 

[CharlieS]

I could be wrong. I wasn't looking that closely at the upper manifold the times I've had it off. I'd trust people that are more familiar than I am.

 

[Malleus]

First, there is a coolant passage in the throttle body. It's there to aid in engine warm up. There is no coolant passage in the intakes, upper or lower.

Remove the throttle body and check it very carefully for cracks. You'll be able to see the coolant passage very clearly by following the tubing inserted into the body.

Second, the bolts are as follows:
Torque is 15-lb·ft for all bolts going into an aluminum thread on the head or intakes, nuts are the same.
The old Toyota part numbering system has the bolt grade, thread size and length in it. These bolts are both a grade 6, M8x1.25 (the pitch is a JIS standard and is not in the part number). The new Toyota part number system uses an anonymous part number; you have to know what it is to know what it is.
The longer is an M8 x 28 long JIS hex head bolt

The shorter is an M8 x 25 long

These bolts are readily available in the dealer warehouses across the US. Talk to your dealer parts specialists about your needs, and make sure you use your VIN and describe exactly what you need. If you only give them a part number, it's up to you to know whether that part number is good or not; they won't bother to try to find where it's used or what has superseded it, unless they're very good, and there are very few of them around.

 

[CharlieS]

A diagram from Partsouq (for my '94 1FZ-FE, can't imagine it matters):

 

[HCP2311]

I pulled the throttle body off and noticed that the top two bolts didn't seem to be as long as they could be and probably only had a few threads in. So possible leak there. The gasket looks like it might have some coolant residue on it. The throttle body on the filter side is COVERED in what I think is coolant residue. I marked what I'm guessing the route for the coolant is and I don't see any cracks, but I also don't really see how coolant could be leaking into the filter side of the throttle body.

 

[Malleus]

The only way for coolant to get into the head from the throttle body is through the coolant passage, and that can only happen if the passage is open to the airstream. Plug one end of the coolant passage and force air or water into the other. If it's leaking, it'll be obvious.

The other way for coolant to get into the cylinders is through a failed headgasket.

 

[HCP2311]

Plug one end of the coolant passage and force air or water into the other. If it's leaking, it'll be obvious.

Yeah, I did that and didn't notice anything leaking. In hindsight I don't actually know if its burning coolant, that's just what I was told. (I was also told at the same time that it had excessive crankcase pressure, and I found about 6 dirt dauber eggs inside the PCV hose The engine was just rebuilt by Southern Cylinder and Head in Huntsville, AL and I've only heard good things about them from people who have used them so a failed head gasket seems strange. The engine hasn't been properly run since the rebuild so I'm thinking I'm going to reinstall the throttle body, oil the cylinders and try to start it. I wonder if the person could have mistaken burning coolant for assembly lube?

 

[CharlieS]

Not sure, but that seems like an odd corrosion or residue in the throttle body. I see oil residue often, but that looks more like corrosion/aluminum oxidation.

 

[Fj80oregon]

Hey if you end up needing a throttle body I have several, I also have all the bolts you would need, I have several Complete intake plenums from rebuilds. Never seen one fail before. The top two bolts on the throttle body do not grab a lot of threads make sure to not over tighten they strip out easily. I would clean up that throttle body and post some pictures of the EGR delete and see if we can spot something wrong. I also have several EGR setups. It will be difficult to put it back to normal without pulling the intake plenum completely. Pictures will really help with analysis,

 

[Godwin]

Yeah, I did that and didn't notice anything leaking. In hindsight I don't actually know if its burning coolant, that's just what I was told. (I was also told at the same time that it had excessive crankcase pressure, and I found about 6 dirt dauber eggs inside the PCV hose The engine was just rebuilt by Southern Cylinder and Head in Huntsville, AL and I've only heard good things about them from people who have used them so a failed head gasket seems strange. The engine hasn't been properly run since the rebuild so I'm thinking I'm going to reinstall the throttle body, oil the cylinders and try to start it. I wonder if the person could have mistaken burning coolant for assembly lube?

Since you're in Huntsville and if you want someone to look it over check with @Zjohnsonua or @RocketCityCrzrs

 

[mudgudgeon]

Yeah, I did that and didn't notice anything leaking.

Another way to find a leak, plug one end of the water gallery, and spray in some brake ckeaner.
Brake cleaner will find its way through a crack, you'd see wetness in the throttle body where a crack is

 

[Malleus]

Well, that would have been a tasty tidbit to know, beforehand. If you've recently replaced the head, I'd look at the headgasket last. I'd also personally verify that there is a problem, before I took anything apart.

When you say it hasn't been running right, how about a little more information, so we can give you some worthwhile help. For instance, how many miles since the rebuild? Have you talked to the engine builder about the problem(s)? I assume they didn't install it? Who was the installer (I assume it wasn't you) and have you talked to them about your problem(s)?

 

[Zjohnsonua]

Thanks for the mention, @Godwin.

@HCP2311, I PM'd you. Let's see about getting this sorted.