86 motors - The 1947 - Present Chevrolet & GMC Truck Message Board Network

greygoose · 08-20-2009, 10:58 PM

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.

fiddy9apache · 08-20-2009, 11:53 PM

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.

85Bowtie · 08-20-2009, 11:58 PM

Quote:

Originally Posted by fiddy9apache

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.

Hoods69BadBowTie · 08-21-2009, 12:22 AM

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.

greygoose · 08-21-2009, 12:45 AM

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?

85Bowtie · 08-21-2009, 01:02 AM

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.

piecesparts · 08-21-2009, 11:46 AM

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.

greygoose · 08-21-2009, 09:01 PM

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.

fiddy9apache · 08-21-2009, 11:30 PM

Quote:

Originally Posted by greygoose

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.

68 TT · 08-22-2009, 09:25 AM

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.

fiddy9apache · 08-22-2009, 11:59 PM

Quote:

Originally Posted by 68 TT

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.

greygoose · 08-23-2009, 11:39 PM

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?

68 TT · 08-24-2009, 11:20 AM

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.

greygoose · 08-25-2009, 01:21 AM

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?

68 TT · 08-25-2009, 11:00 AM

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.

08-20-2009, 10:58 PM	#1
greygoose Registered User Join Date: Mar 2008 Location: N.C. Posts: 250	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. __________________ If it ain't a chevy,I don't want it

08-20-2009, 11:53 PM	#2
fiddy9apache Registered User Join Date: Aug 2009 Location: ftw tex Posts: 682	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. Last edited by fiddy9apache; 08-20-2009 at 11:55 PM.

08-21-2009, 12:22 AM	#4
Hoods69BadBowTie Chevys Kick A$$ Join Date: Jan 2005 Location: Zootown, MT Posts: 12,699	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. __________________ HOODS is what I answer too -'79, '77, '88 Pickup Sold, '85 Camaro, '83 T/A, '81,'83,'90 K5 Blazer All Sold -'79 3/4 ton "Big Yellow Bananna" Lifted 4spd. 39.5 TSL Swampers, The money Pit -'86 K5 Blazer Silverado 6.2 4" lift 35"s -'95 Ext. Cab Shorty 4" Tuff Country rolling 35" M/T's -'83 Monte Carlo T-Tops. 126,500 Original Miles -LATER I would rather push a Chevy then drive a ford!!

08-21-2009, 12:45 AM	#5
greygoose Registered User Join Date: Mar 2008 Location: N.C. Posts: 250	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? __________________ If it ain't a chevy,I don't want it Last edited by greygoose; 08-21-2009 at 12:45 AM.

08-21-2009, 01:02 AM	#6
85Bowtie Registered User Join Date: Mar 2009 Location: TN Posts: 410	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. __________________ '69 Dodge Charger R/T 440, 727, 3.55 Sure Grip '68 Plymouth Road Runner 383, 727, 3.23 Sure Grip '89 Dodge Diplomat ex cop car 408, 727, 3.55 Sure Grip '77 Dodge Monaco ex cop car 440, 727, 2.71 '79 Dodge 'Lil Red Express pickup 360, 727, 3.55 Sure Grip '12 Dodge Challenger SRT8 392, M6, 3.92 '85 Chevrolet C-10 SWB 2wd 305, TH350, 2.73

08-21-2009, 11:46 AM	#7
piecesparts Parts and more parts Join Date: Nov 2003 Location: Lebo, Kansas (middle of nowhere Posts: 6,821	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.

08-21-2009, 09:01 PM	#8
greygoose Registered User Join Date: Mar 2008 Location: N.C. Posts: 250	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. __________________ If it ain't a chevy,I don't want it

08-22-2009, 09:25 AM	#10
68 TT Still plays with trucks Join Date: Jul 2009 Location: Spokane, WA Posts: 3,556	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.

08-23-2009, 11:39 PM	#12
greygoose Registered User Join Date: Mar 2008 Location: N.C. Posts: 250	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? __________________ If it ain't a chevy,I don't want it

08-24-2009, 11:20 AM	#13
68 TT Still plays with trucks Join Date: Jul 2009 Location: Spokane, WA Posts: 3,556	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.

08-25-2009, 01:21 AM	#14
greygoose Registered User Join Date: Mar 2008 Location: N.C. Posts: 250	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? __________________ If it ain't a chevy,I don't want it

08-25-2009, 11:00 AM	#15
68 TT Still plays with trucks Join Date: Jul 2009 Location: Spokane, WA Posts: 3,556	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.



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.