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Old 08-20-2009, 10:58 PM   #1
greygoose
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86 motors

I just couldn't pass up this truck it's an 86 deluxe ,but the motor is weak,so I talked to s bud that says he had one brand new and that over time the motor got clogged up.And says that,that's what's wrong with mine.Ifs that's the case how do I fix it and how do I prevent if from happening again.
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Old 08-20-2009, 11:53 PM   #2
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Re: 86 motors

i say the whole reason its weak is...
A. its a lo-po 305
B. the quadajet is prob worn out
C. broke vacuum lines.
---------------------

i would replace the intake with an aftermarket and go with a nice carb, 600cfm will be enough.


i guess if you wanted you could run seafoam though the engine or pour water down the carb at high rpm to break up carbon.

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Old 08-20-2009, 11:58 PM   #3
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Re: 86 motors

Quote:
Originally Posted by fiddy9apache View Post
i say the whole reason its weak is...
A. its a lo-po 305
B. the quadajet is prob worn out
C. broke vacuum lines.
---------------------

i would replace the intake with an aftermarket and go with a nice carb, 600cfm will be enough.


i guess if you wanted you could run seafoam though the engine or pour water down the carb at high rpm to break up carbon.
I agree, really nothing to "clog up" on an engine. It could probably use a valve job by now. Your cam and timing chain is probably pretty worn by now too.
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Old 08-21-2009, 12:22 AM   #4
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Re: 86 motors

Ya I would do a complete tuneup. Check vaccum leaks and such and check out your carb. Then go from there and see if you can get it running better and do a rebuild or swap motors out.
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Old 08-21-2009, 12:45 AM   #5
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Re: 86 motors

Thanks guys ,I think I'll start with the sea foam and let you guys know how it goes.Question can I put it in the engine and in the carb at the same time?
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Old 08-21-2009, 01:02 AM   #6
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Re: 86 motors

It works properly added to the gas tank, so I wouldn't flush it straight down the carb.

Alot of people say it works great, I've used it and haven't noticed any improvements whatsoever on several vehicles I've owned. So you'll have to let us know what it did for you.
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Old 08-21-2009, 11:46 AM   #7
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Re: 86 motors

How many miles on the engine? What is your timing set at? What condition is your exhaust in? A plugged converter or too low of a timing setting will affect your performance.

Seafoam will help, as will Rislone additive. I have done what we always called a "Liquid valve Job" to remove carbon from the tops of pistons on many older engines, but there are those that think the world would come to an end doing it. That is the pouring of a fluid down the carb at a very slow rate. It does work, though no matter what one may think.

A good cleaning of the fuel system components, replacement of the distributor cap and rotor along with good quality plugs and wires will make a very noticeable difference. Not sure about your smog laws---setting the timing slightly advanced will give a better throttle response. Change out the 305 to a 350 will give it a good boost, also. we tooke the engine out of my Son's 86 and replaced it with a 350 and we are not sorry that we did it.
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Old 08-21-2009, 09:01 PM   #8
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Re: 86 motors

Ok today I got a little busy but I was able to do some ole fashion cleaning inside the motor. lol I ran a gallon,half and half diesel and kerosene and ran a little through the carb too,then changed the oil and filter.That's all I was able to get done today.It seem to run a little better.Tomorrow I'll change the plugs,wires,cap and rotor and see how that goes and report back to you guys.
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Old 08-21-2009, 11:30 PM   #9
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Re: 86 motors

Quote:
Originally Posted by greygoose View Post
Ok today I got a little busy but I was able to do some ole fashion cleaning inside the motor. lol I ran a gallon,half and half diesel and kerosene and ran a little through the carb too,then changed the oil and filter.That's all I was able to get done today.It seem to run a little better.Tomorrow I'll change the plugs,wires,cap and rotor and see how that goes and report back to you guys.
sounds good, now do it with water before you change the plugs out. and dont waste your money on expensive plugs. ac delco or autolite will work just fine.
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Old 08-22-2009, 09:25 AM   #10
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Re: 86 motors

Don't forget a cam upgrade while you have the intake off. That era of engines was very prone to eating cam lobes and the cams were wimpy to start with. The worn out cams are what gave them such a bad reputation.

I put the Crane compu cam 2040 into my 83 vintage 305 along with a Performer RPM intake and 600 Edelbrock carb. Wow what a difference. It made great power and had just a little lope to it. The thing sounded great and ran even better.
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Old 08-22-2009, 11:59 PM   #11
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Re: 86 motors

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Originally Posted by 68 TT View Post
Don't forget a cam upgrade while you have the intake off. That era of engines was very prone to eating cam lobes and the cams were wimpy to start with. The worn out cams are what gave them such a bad reputation.

I put the Crane compu cam 2040 into my 83 vintage 305 along with a Performer RPM intake and 600 Edelbrock carb. Wow what a difference. It made great power and had just a little lope to it. The thing sounded great and ran even better.
thats a perfect set up, not over carb'd or over cammed.
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Old 08-23-2009, 11:39 PM   #12
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Re: 86 motors

ok got around to changing the plugs wires.etc today.advanced the timing a little too,ran a lot better.And yes 68TT that will be the next thing i do but only this time i'm gonna leave the Q-jet carb on with a spacer.Being that I'm hearing that they are almost as good as any aftermarket carb....what yall think?
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Old 08-24-2009, 11:20 AM   #13
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Re: 86 motors

The CCC Q-Jet was definitely a restriction. I tried it your way with the stock carb on there and it would barely chirp the tires going into second. With the 600 Edelbrock it would literally spin the tires on the shift.

Maybe re-jetting the Q-Jet would have helped but they are such a pain to take apart and get to work right after reassembly that it wasn't worth messing with to me. I had the Edelbrock sitting on the shelf so I gave it a try and never looked back.
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Old 08-25-2009, 01:21 AM   #14
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Re: 86 motors

OK thanks 66 TT. Now today I took it out and got it out on the highway and guess what...When I punched it it took off fine but then the rpm's just dropped,it wasn't the trans,because the rpm's didn't go up.And I don't think it was the carb,because when I put it in neutral,it revved up fine. It would not go over 45 unless I lightly applied gas.So my thinking is that the converter is clogged up real bad,plus the muffler is bent up as well.Or do you guys think it might be something else?
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Old 08-25-2009, 11:00 AM   #15
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Re: 86 motors

I had a catalytic converter come apart and spit chunks of the honey comb down stream in the exhaust system once. It ended up with a big piece wedged into a bend just before the muffler and stopping the motor cold.

If your exhaust is in bad shape try fixing that first so you are not pulling your hair out trying to figure out what is wrong with the engine when it may not be in the engine at all.

Good luck.
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