Crappy running 85 GMC.

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HotRodPC

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85 K20 LWB
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454 - Turbo 400 - 3.73
That hurt dammit. You're not trying to acuse me of abuse of power are you??? I didn't think so.!!! But, I better refix it now that you seen it and I gotta bail to do the part time thing. !!!!! :wave: :wave: :wave:
 

89Suburban

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That hurt dammit. You're not trying to acuse me of abuse of power are you??? I didn't think so.!!! But, I better refix it now that you seen it and I gotta bail to do the part time thing. !!!!! :wave: :wave: :wave:
:roflbow:

:wave:
 

Irishman999

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Update on the 85 and its long list of issues. Same old ****, it runs great up until a point and then stumbles, hesitates and refuses to idle nicely.

The other day I found a new timing light on craigslist for 10 bucks so I picked it up on my way home. I was showing my wife how they work last night and noticed my timing was really off. I set it closer to the first notch, so I retarded it. I tuned the carb again and adjusted the idle.

Now while its idling if I quickly crack open the throttle it does not hesitate. I drove it around in the alley and it seems to be fixed! Im going to take it on a trip to the dump this morning and at some point today drive it to Carson City to pick up my solvent tank, I will report back with results.
 

Irishman999

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Good deal man, hope that fixes it!

Me too man, I've been looking into an upper engine rebuild or a crate motor because this thing is running so ******. If its a decent runner now I can focus on so many other issues that are driving me crazy with it.

First is the wheel bearing or whatever it is causing the noise in the front end.

Second is the steering box leaking power steering fluid everywhere I park it.

and of coarse the paint, or lack of paint.
 

crazy4offroad

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Me too man, I've been looking into an upper engine rebuild or a crate motor because this thing is running so ******. If its a decent runner now I can focus on so many other issues that are driving me crazy with it.

First is the wheel bearing or whatever it is causing the noise in the front end.

Second is the steering box leaking power steering fluid everywhere I park it.

and of coarse the paint, or lack of paint.

You can knock out the wheel bearing issue in an hour or 2.

I put new seals and o-rings in my steering box, so it's not impossible but the hard part is getting it off the truck and back on. You can do this in 4-6 hours.

Paint schmaint, who needs it! LOL actually I was thinking of painting mine black again, I miss it! My dad is pretty good at it and is giving me tips.
 

Irishman999

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Yeah the wheel bearings should be easy. Im planning on replacing the races while I have the hubs off. Since Im going to have a solvent tank at some point today so Im going to make a big ass project out of the wheel bearings. Im thinking about cleaning and wire brushing everything and painting the hub black.
 

HotRodPC

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Cool. Hope its fixed and at least patched up to run till you find you a good used 3Fitty for a good price. I'd ship you a steering box, I think I have a spare one, but its for 2WD and I am pretty sure the tubafo and the fobafo use differant boxes due to the pitman arm positioning.
 

Irishman999

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Cool. Hope its fixed and at least patched up to run till you find you a good used 3Fitty for a good price. I'd ship you a steering box, I think I have a spare one, but its for 2WD and I am pretty sure the tubafo and the fobafo use differant boxes due to the pitman arm positioning.

Thanks for the offer dude! You are right about the pitman arm. 4x4 pitman arms run parallel with the front axle and 2wd pitman arms run intersecting with the front axle.

The one I have is fine, its still tight and the truck does not wander. The only problem with it is the seals, everywhere I park I leave a puddle about a foot wide. Im really tired of buying atf for it.
 

HotRodPC

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I need to figure out whats wrong with the power steering on the 85K10. Sometimes is just gives up and its like the belt it off the pump. No squeeling, no leaks, no whining, all sounds normal, but about 50% of the time, its like steering wo a belt. Its very hard to steer. I have a feeling its been this way for along time and that's why the steering column is loose from having to yank on the steering wheel so hard.
 

Irishman999

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Update on the truck: I drove the **** out of it today, first mission was to the dump for free dump day and the truck ran great.

Second mission was a 100 mile long trip to get my parts washer. the 85 was still running great except for a really slight bit of hesitation. It seems like the more I drive it around the smoother it gets.

Now the ****** part of the story. I ran out of gas between 2 towns, basically I sat on the side of the road for a few hours until I got a hold of a good buddy to bring me some gasoline.

Parts washer is awesome, I need to put a pump in it but looks to be great quality and very usefull.
 

RailRiderHD

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great to hear man, sorry about the running out of gas part, lol. When I get my shop built a pressure washer like that is one thing on my want list!
 

Irishman999

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great to hear man, sorry about the running out of gas part, lol. When I get my shop built a pressure washer like that is one thing on my want list!

The running out of gas thing was stupid. We just left a gas station and I considered filling up before we left Washoe Valley, I did not get any gasoline because I just put 20 in before leaving Reno.

I got a solvent tank today, I have a pressure washer but its at my parents. Im trying to talk them into coming up to visit and bringing the rest of my tools! Between a solvent tank, pressure washer and wire wheel on a grinder you can do some really quality clean work.
 

Irishman999

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Well, as I have bitched about numerous times before.... my 305 has a deadspot and has always not run completely right. I have been chasing the problem for a while now and our combined conclusion was valve train problems.

Crazy4offroad posted a vacuum trouble shooting chart a few times and I always meant to put a vacuum gauge on the truck but never did until now....

My dads shop is filled with everything, I just walked over to a shelf full of diagnostic tools in cases and found a vacuum gauge and fuel pressure gauge. The last 60 miles of my trip the truck was STARVING for fuel and did not want to go anymore.

I took the top off my carb and blew everything out with a blow gun to make sure there were no clogs like last time. I put a new in line fuel filter on and hooked the fuel pressure gauge up, it was reading 5.5 pounds at idle so I think it should be fine now.

For ***** and giggles I put the vacuum gauge on at the needle was bouncing at 15 Inch pounds. When you increase RPM's the needle gets steady but does not go as high as it should. All signs are pointing to compression loss. I tried adjusting the idle screws but they were already as good as they could be and affected the vacuum NONE.
 

HotRodPC

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SO you've got some leaking valves huh??? The good news is, you're leaking vavles won't leave you stranded. They will hurt performance and hurt mpg, but won't leave you broke down on the side of the road. You know what you gotta do. Eventually, you need one of those GM $1300 crate motors. I have to say, I'm fairly impressed with my 85 K1500's performance, and so far, I am exstatic with the mpg. I put $20 in the 84 C20 and it last about this long, I put $20 in K1500 and its seems I get over 1 1/4, closer to 1 1/2 the distance. Maybe I'm just not driving as much, but is sure seems I don't stop for gas near as often in the K1500. 2 factors, Small Block vs Big Block, and 3.73 gears vs 3.21 gears. Those 3.73's are much peppier taking off and most of driving is in town. :waytogo: I still think my 84 C20 with the 454 will do much better with 4.10's. And your truck with a manual trans, oughta do even better in mpg.
 

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