Level of effort - intake/carb swap?

[Jaybr]

I have 2 Broncos, 76 and 74. The 76 has had carb issues (stock) since before I purchased it. PO gave me a rebuild kit with the truck and told me it had a tendency to flood and leak fuel. I rebuilt the carb and drove it a bit and it was fine, sat a couple months and flooded at startup leaking fuel all over the top of the motor. I rebuilt it a second time and same thing happened after sitting a while. I have a crate motor with Holley sniper that will eventually make it's way into the truck, but due to constant carb issue we don't drive it, it's just sitting waiting for me to get to the restoration.

The second truck is a 74, and while it had a lot more issues than the 76, the carb setup was not one of them. Never had an issue with starting or flooding. This motor has a Edelbrock Performer 289 intake and carb.

I've got the 74 body off and will be pulling the motor this week. I'm giving the motor and trans to a good friends son who has a frame and title and is collecting parts to build a bronco. What I'm wondering is what is the level of effort to swap the performer intake to the 76? Is it an afternoon of work or a weekend? The 76 has an electric choke and the Edelbrock is manual, is that just a matter of running a cable and maybe knob in the dash, or can I use the "throttle" knob?

It would be nice to be able to drive the 76 some if I can get it reliable, but don't want to waste a bunch of time when I'm planning to strip it to frame and replace motor in a few months.

 

[tbratz]

I just pulled the Performer intake on my '69 to fix a leaking gasket and it only took about two hours. Most of that time was just cleaning off the old gaskets and dropping the distributer back in. The best advice I can give is to not use the cork gaskets that go across the front and back of the block, just use a thick bead of sealer. On my Bronco it has both a choke and throttle "knobs" and I do not think you can use your throttle knob since I believe the cable will be too short. On my '74 Highboy I bought a generic throttle cable from Autozone, drilled a small hole in the dash for it and ran it to the manual choke on the carb and it works fine.

 

[Jaybr]

Thanks,

I watched a couple YouTube videos and got the tip about using RTV instead of the cork gaskets. Are there any worries about stuck bolts, breaking bolts off, that sort of thing? Not sure if that’s a common problem with these or not but those issues always take more time than the original job.

Can I just mark the distributor position and reinstall to marks or do I need to rotate to TDC and go through that whole process?


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[tbratz]

I have never seen a frozen bolt that broke on an intake, but there is always that chance. I have worked on many 302's over the years and this is my experience anyway. Yes, you can just mark the distributor housing and block and put another mark where the rotor points on the distributor housing and then slide it back in lining up both marks. Just remember that when you pull the distributor out it will rotate the rotor a little bit, so you have to make sure when you drop it in and it engages the cam gear it rotates back to your mark.

My problem was the distributor doesn't always drop all the way down and you have to bump the engine a few times while pushing it down, for it to fully seat, which is kind of hard by yourself.

 

[m_m70]

You don't have to take the dizzy out to swap manifolds. And I never had an issue with breaking the bolts but hey, it's a bronco......anything can happen. Usually takes me a couple hours to RnR with the most basic of tools. Make sure you cover the holes and valley when cleaning the gasket surfaces and make sure you remove whatever you cover the holes with out before re-installing. Seams obvious but it has happened!
You can just run a generic choke cable from any auto parts store for the manual choke. Thinking they're around 15 bucks.

 

[Jaybr]

Thanks,

I think I’ll go ahead and do it and maybe get to drive the truck some before I tear it down.

I can pull the choke cable and knob out of the 74 once I get the body off the lift, won’t need it with the sniper setup on the new motor.


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[m_m70]

Great! Make sure you use the felpro 1250s-3 intake gasket and NOT the 1250.
Google it and you'll see why not.
Enjoy the ride!

 

[Jaybr]

Great! Make sure you use the felpro 1250s-3 intake gasket and NOT the 1250.
Google it and you'll see why not.
Enjoy the ride!

I guess I picked up the wrong one, I got 90361 which is for a 77.

Felpro list 90103-1 as the correct gasket..

I looked up the 1250s and see why it’s recommended and I’ll have to track one down.


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[B RON CO]

Hi, it important to use the correct gaskets, especially with an aluminum intake manifold. Aluminum intakes are famous for leaking were the intake ports are near the valley.
I never had trouble with the rubber end gaskets, and have also used silicone with good results. If you decide to use the end gaskets, just dab a small amount of silicone in the corners, this should be in the instructions.
Many guys use 4 pieces of 5/16 threaded rod as guides to hold the gaskets in place and help lower the manifold home.
Good luck

 

[Rustytruck]

You break the bolts going in on intake bolts not going out a 5/16 thread in a weak bolt easily breaks at 40 foot pounds which is far higher than the torque specks on the intake bolts. but not high enough for a good bolt.

 

[Jaybr]

started disassembling the motor with the Edelbrock and the distributor is stuck. That one really doesn't matter since I'm not going to reinstall the manifold fully, but hope the other comes out ok.

 

[Bitch'nBronco]

You can leave the distributor in place when swapping intake manifolds. Might help to take the water neck off the intake but I usually leave it and just swing it back behind the distributor

 

[pcf_mark]

You can leave the distributor in place as BitchnBronco said above. I take it would take it out so I can get at everything but this is not my first rodeo. If you do want to take it out and it is stuck take the clamp off and the cap off (leave wires on the posts) and just crank it around. That will pop it up and loosen it up. I try to get the engine to TDC by aligning the balancer line with the timing mark. Then before I take the distributor out I find #1 spark plug wire post on the cap and put a line on the distributor base with a sharpie and #1. Then when I lift the distributor out I watch where the distributor rotor is pointing AFTER coming out. and mark that with a sharpie and the "#2". The gear on the dist is helical and the rotor will move 20 degree or so. As long as you do not crank the engine once the dist is out you can position the rotor at #2 line drop it in then align then twist the body to align the rotor with #1. Should be very close and it should start w/o backfiring and drama.