FJ60 only runs at full choke. (1 Viewer)

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Feb 18, 2018
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Location
Niceville Florida
I have a 1984 FJ60. It ran good but had a pretty good exhaust leak so I decided to replace my exhaust manifold gasket. I got it all back together after a couple of weeks and fired it up. It will only run at full choke now. I’m about ready to just take it to the shop but thought I’d post on here as a last ditch effort. It is not de-smogged so I labeled each little vacuum line and ensured they all went back where they belonged. I’m pretty sure it’s an original carb. I replaced the carb gaskets with new cork ones. I suspected a vacuum leak and sprayed carb cleaner but don’t see it sucking in anywhere. The carb selenoid is kicking on when the key is turned.

Are there any specific hoses that I should check thoroughly? Any other ideas? Thank you.
 
Here are pics from under the hood...

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broken gas filter ...causing a vacuum leak from your intake. here:

View attachment 1856083
The OP said he’d sprayed carb cleaner everywhere. Did he miss spraying around the gas filter or does a broken gas filter not respond to carb cleaner?
 
What gasket did you use? Also, did you resurface your intake and exhaust manifold when you had it off?

In my experience, the most likely cause of a leak that requires full choke just to maintain idle, is at the manifold union.

Sometimes the carb spray trick fails because people just feather the spray lightly and the fan blows it away before the leak has a chance to suck it in.

Have a fire extinguisher handy. Put the straw in the can and hit that joint from the top and from underneath the truck. Give it a good spray. Stay away from the distributor. In fact, just avoid that entire side. There’s only a few places that can leak over there, and it’s easy to verify by sight.

Also, hit the base of the carb with some spray too. That’s another common area. If you still cannot find the leak, you may have a cracked intake manifold.

Also, if you have to remove your manifold again, definitely have it resurfaced and have the bolt holes spot milled so they’re all level as well. It might be a challenge to find a machine shop that can do the job, but be persistent and you’ll find one.

When you put it all back together, use a remflex gasket. And retorque the bolts after the first few hundred miles.
 
I did have the manifolds machined. I used a new FelPro manifold gasket because I’ve read a ton of reviews that the Remflex tend to delaminate and leak rather quickly. My manifold bolt holes looked nice and level also. Torqued the bolts to spec. The gas filter has been broken since I got the Cruiser but it always ran fine before so I didn’t think it would cause this issue. Yes the solenoid wiring is sketchy. It still clicks over though and I ordered a pack of new connectors to fix it. I may be spraying the carb cleaner too light because the fan was blowing it around quite a bit. I’ll try spraying it with the straw a little heavier when I get home today and see what happens.
 
Great man. Sounds like you’re doing all the right things. If you don’t already have a vacuum gauge, pick one up on the way home. They’re about $15-$20 at your local auto parts store. This will help you to diagnose your problem.

You can plug off the leak in the gas filter temporarily, as you track down the other source of your leak. That’s a moderate leak for sure, but my guess is you have another leak somewhere else.

On the distributor side, about the only vacuum source big enough to cause stalking is the PCV valve fitting and the T-Junction just above it. Give it a quick visual inspection to make sure everything is secure.
 
Ok, so I found my leak. It’s leaking all around then manifold gasket but most of the leak is toward the firewall. I had the manifolds
machined and used a new Fel-Pro gasket. I also toqued in the correct pattern to spec. I’m not in a spot to machine the engine side right now. So I have some decisions to make. I have a new RemFlex gasket that is about twice as thick as a FelPro and is known to seal better but supposedly doesn’t last as long. I also could use a high temp copper sealant on both sides of the gasket (comes in a tube from the auto parts store, rated at 700 degrees and has a pic of headers on the package). Should I go RemFlex with the sealant? I really only want to rip this all apart and do it once. No time for games. Any suggestions or advice would be greatly appreciated.
 
This might be a time when a Remflex is warranted. RemFlex recommends no sealant. Follow remflex's torque recommendations carefully.

If you do use a sealant, DO NOT USE the high-temp stuff in a tube. It won't work for this.

Use the shellac-based stuff in a can that is brush on. None of the spray stuff will work. This stuff bakes hard as Nancy Pelosi's face.

Apply to ALL sides - Cylinder head, gasket, manifolds.

1900241
 
Try retorquing the manifold bolts befor you go to far down another rabbit hole. I actually give them a few extra foot pounds of torque over spec too. They do tend to loosen a bit after a few hit and cold cycles.

In my experience, the Remflex is the only gasket that has worked for me. Even with that, I’ve had to tighten the bolts up when it starts to leak. Don’t bother using any sealant. Just tighten those bolts from time to time and you’ll be fine.
 
did you re-torque after heating and cooling cycles?
I'll do it for a few days until there is no more movement
 
Yes, I replaced the gas filter. I never did get a good seal on the manifold so I don’t think running it through heating and cooling cycles will help a lot since it never had a good seal to begin with. I could see if it started out good and slowly got worse the it might need to be re-torqued again.
 
Well... I’m not sure what to tell you buddy. If you have resurfaced the manifold, and you’re confident that they did a good job, and you still have not been able to get it sealed, then you’ve got a problem.

You’ve identified the leak is toward the firewall side of the manifold. For $hits and gigs, just give those bolts a good turn to maybe 10 foot pounds over spec. Then crank up the motor and check your vacuum. If you’re still loosing air, hit it with carb spray again to verify the location. If it still isn’t sealing, you have one or more of the following issues:

1. The manifold was not resurfaced properly. Take it to another machine shop to verify.

2. The bolt holes were not spot milled properly and you’re not getting even pressure against the intake and exhaust union. You can cut som washers in half to try and even it up a bit, maybe use some brass washers and crush them down on the bolts and hope it works, or take it back to the machine shop and have them properly milled.

3. You have a cracked intake manifold. The machine shop would probably have noticed this, but maybe they missed it.

4. The head could be warped and needs to be resurfaced. I doubt it, but it’s possible. You’d need to pull the head and take it to a machine shop and have them verify.

5. Verify that the leak is actually at the manifold. It could be at the base of the carb. Tighten up the four bolts at the carb base to be sure.

I’d just put a remflex gasket on there and torque it down, then tighten down the carb. If that doesn’t work, part it out haha
 

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