Installing Intake Manifold on 4.3L Merc?

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seachunk2

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I installed rebuilt heads on my 85 4.3LX. I have a 4bbl Weber carb. I am using a fel pro head gasket kit. The kit has these metal plates that somehow are to be installed on the intake gasket. I don't know what they are for and if they are applicable for my particular motor. I do have a carb choke system that in mounted on the intake starboard side. As the engine heats up the coil within the mounted pieces opens the choke via a connecting rod. Sorry if I am explaining things poorly. I'd appreciate any help that explains what these restrictors are for and if I need them. They might be used for a cross over system but I don't know else about such a system. Thanks!
 
My advice is to use the exact same style gaskets you took off. If the new ones look different, you got the wrong kit.
 
Unfortunately I don't have the old intake manifold gaskets to reference. However, I took a closer look at the restrictors included in the kit and was able to attach them to the gaskets without any issue. From what I can tell in my searches, these restrictors help with warm up the motor.
 
OK you must have the pre-vortec engine same as mine. 12 bolt intake vs 8 on the vortec. The restrictors were on my old gaskets I took off. I believe they are there to limit the amount of exhaust gas passing through the exhaust cross over, enough to heat the thermostatic spring but not so much to overheat the carb and cause vapor lock. So I'd say use them, although I will say that the choke opens up pretty slow with this design, since these engines run a lot cooler the automotive engines they are based on. That choke design (called the divorced choke because the spring is separate from the choke assembly, sitting on top of the exhaust cross over in the manifold) was used on GM cars for many years dating back to the late 60s all the way up to the mid 70s when they began to switch to electric heated chokes.
BTW Fel-Pro hosts a good forum on their site and you can ask this question there and get a pretty quick answer.

https://www.dropbox.com/s/1yyytu26xgohers/IMG_2211.JPG?dl=0
re-man heads installed

https://www.dropbox.com/s/px3e829ygbmoyt5/IMG_2235.JPG?dl=0
top end all put back together

Other tasks you will have to figure out is installing the distributor properly and adjusting the hydraulic valve lifters correctly. Not hard just a bit confusing the first time you do it....

PS I'm not so sure you have a Weber carb, in that year range Mercruiser was still using Quadrajets and the Weber as far as I know used an electric choke. But there are all kinds of variations I guess....
 
LouC, thanks! I definitely have a Weber Carb. I visited the Fel Pro forum and it is indeed very informative. Gotta save that as a favorite. As far as the lifters, on my engine the rockers just get torqued down to 20 ft.Lb. I have the Mercruiser Service Manual for my engine and I am referencing that. If I understand correctly, there are some 4.3L heads with valves/lifters that need to be adjusted for lash but mine aren't that type. I don't know what the difference is to be able to better explain. The Boss and my daughters are having a garage sale today but when they wrap things up, I intend to fill the crank with some oil and prime the oil pump. Then I will check compression. I have my fingers crossed that compression is good in a 6 cylinders. If so I will toss on a new set of plugs and toss on the intake manifold. Then reach deep into my pocket and spring for new Mercruiser exhaust manifolds and risers. The 5 year old HGE crapped out and here I am. Can't really blame HGE. It seems that these parts only last about 5 years so I was due. I thought I'd be able to get more since I trailer and flush after every run. Seems like that doesn't matter. I think the biggest problem is simply not using the boat enough.
 
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