The Stovebolt Site Forums The Parking Lot '60-'66 Trucks Any advice from rebuilders out there?

Well, I'm sort of in a jam. I'm certainly no expert, but I'm no greenhorn either but I can't decide what I should do. I purchased a 1962 GMC stepside longbed with the story that the V6 in it would get up and go but cosmetically it had some problems. Being a body guy, I figured this fit the bill perfectly. The problem is now that I've had a trusted mechanic take a look at why I can't get it down the road (she cuts out like nuts, one cylinder is missing and the clutch acts goofy). I've only got a few thousand tops right now to either try to fix 'er up or cut my losses now, OR drop in a different engine. The only guy I know that has time to tear into this poor ol' gal says he only wants to work on Chevy stuff '65 and up, and I'm thinking I may have to do this myself..Any opinions? I'm wore out from thinking so much about this over the last few months and was wondering what some of the nice folks over here think...what's some thoughts here on rebuilding a "345" 1962 1000 series GMC stepside engine, or would it be too costly to maybe put in something new that will link up, or maybe just say forget it and sell to someone with more financial resources? I'm sorta taking a poll here...I sure wish I could save this truck!

What did the mechanic decide was wrong with the engine?
I don't think those old v6s were designed for get up and go. More like get down and haul I think. And not a$$.

He just looked it over and was saying, "It's going to need some attention", but he didn't want to commit to it since he has several "antique" vehicles on his lot now he doesn't want to have to mess with. You know, I'm thinking that I should start myself: Complete change out of all the stuff I know how to do, carb, points, plugs, wires, fluids etc. etc. I can tell you from trying to get it down the road, 1st gear has little to no power and the truck pops, burps, backfires like mad and seems to have little power other than sporadically. Hey, thanks for your response and for talking with me!

Could a small block Chevy be dropped in to the truck at a reasonable cost or is this a ridiculous notion?

Has it been sitting a long time? Maybe carb issues. Valve problems will cause some if not all of the symptoms you describe. For starters get those valve covers off and see whats going on there. What transmission does it have? Three on the tree or floor shifter? If its floor, you're goin' nowhere fast in 1st. Thats for starting out with a heavy load or pullin' tree stumps.
A small block is not a ridiculous idea. In fact, you'll probably see more V-8s than anything else in them nowdays. Most dont seem to want the original engines.
Oh yeah, welcome to the 'Bolt. Others with much more knowledge than me around here. Be patient and you should get some more responses.
Jeff

Don't give up yet Rondo. The fact the engine runs is a good thing. Give it a tune up, check the plug wires to make sure they are correct with the firing order. Maybe go through that carb too. After you get it running better, do a compression test and also see what kind of oil pressure it has at idle and at about 2500 rpm. That will give you an idea on the general health of the engine. You most likely have a hydraulic clutch. Check the fluid first then go from there.

Thanks a ton Miner54! I'm thinking the same thing...I think I'm just mentally drained and hurtin'-for-certain. I was a naive fool to think that a 50 year old truck would be a daily driver without problems right out of the chute. This thing was hard for me to pull off just trying to get it to Texas from Montana. I'm not going to give up, I'm gonna tune 'er up and see what happens! Thanks for the checklist...I think I'll start this weekend with the plugs, wires and clutch fluid and carb.

jmoore: she's 4 on-the-floor on the tranny. Your point about 1st gear is well-taken: Maybe I'm just not used to the way that feels..once I hit second it starts to move though with problems. IT HAS been sitting a long time! Now that he told me. What should I look for with the valves? You mentioned it could be valve issues...

Thanks!!

I purchased a reprint of the 4" thick manual for this truck...heck, what's wrong with me? I'm going to get out there and get to working on it.

Sometimes they 'll get gummed up and stick in the position they were in when parked x months/years ago. With the covers off, look for them to all be opening and closing all the way. If they were stuck, you could have bent pushrods. I'm really not familiar with that engine.

Thanks for the valve advice. That will be on the checklist for this Saturday.

Man, thanks a ton everyone. I just needed some friends right now! Harrowing messing with this whole process up until now...just trying to convince my wife that it will be alright and then to find out there's a ton more than meets the eye is pretty rough. Ha!

Whoa Pard! Lets slow down for a moment everyone! Bent valves? As stated, the engine runs. Good. Fuel system should be first on the list. Get the tank and lines and filter cleaned up. Then if no improvement, then get a carb kit for the carb. There is no GMC 345 by the way. It's either a 305 or a 351. Then once the fuel is clean, then twist in some new plugs, but not before you have cleaned up the fuel system. Then points and condenser, etc. After that, how's it running. Still crappy, THEN it's time to investigate further. A new clutch may not be a bad thing. Slow and steady as she goes.:) It sounds like the mechanic is intimidated. You need a real old timer who really wants to get in there and mess something up....I mean fix it!

One thing that hasn't been mentioned yet but you need to add to your list of things to do...... Check the timing! If it's way out of whack you can get a lot of popping and low power. Start with the easy tune-up stuff and work your way up. Be patient and you will have her purring like a kitten in no time. Also, don't start out in first gear unless you have a huge load on the truck. You should be able to start out in second gear.

First thing I would do is check the condition of the engine. I would run a compression test to make sure all the cylinders are there first. If it has good compression, then it can be tuned to run well,
Scott

Yea, that's what I thought and put the "345" in parentheses. That made no sense to me either. I need to clean the engine and see what I have...I figure a 305. k10, your sequence of events there are perfecto and what I'm thinking. I can't keep the thought from my head that the fuel system is the story here. I'll eventually do a compression test too. Funny you mentioned the "old timer" to get in there and fix it, 'cause I found a guy right down the road and I'll be talking to him in a few minutes! Comes highly recommended and I'm told he loves this stuff. If he can't do it for some reason, then I'm gonna have to go at it. Which ain't so bad...I'd rather be under the hood now instead of waiting till next month when it's 103 degrees and 99%humidity here it Texas!

Rondo:
Those GMC V6's are built to last. Have a read on this site for the most comprehensive discussion of them. Sign up and you can use their discussion board that is a terrific resource. I have a 1966 GMC with the 305 V6. The advice above is very good. A fuel clean up, tune up, oil change and a compression check are very much in order. Once you have that information, let us know how it went and we can advise from there.
regards,
Steve
New Orleans

http://6066gmcguy.org/

..and yes, work my way up to the timing..gotcha! Thanks. Part of the problem here is my lack of experience with this particular engine. Starting out in 2nd instead of first, as you pointed out: It didn't occur to me that 1st would be for heavy load pullin', which is why "haul" not so much "go" was pointed out in an earlier response. Okay, now that makes some sense and solves some stuff in the process! At the expense of sounding like a moron, I'm no expert and far from a weekender even. It's been years since I've messed with stuff like this, and I must confess my dream of finally owning a ride that is vintage is only just now happening at 43...sad, I know but "wives and lives"..that's my excuse! ha.

If it were mine, and I did not understand mechanicals of the vehicle, the last thing i would do is go ripping the carb apart. First, do a compression test to see if you have comparable compression on all cylinders. If they are OK, then make sure the fuel delivery is clean (ie gas tank, lines, fuel filter, fuel pump). Make sure your gasoline is fresh and is not contaminated. Then get the points, plugs wires and timing done. Then go to the valve adjustments. You could put this ahead of points, plugs, etc. but with no experience, valves can be confusing too. Then go to the carb. Unless you know for sure that the carb is a problem, leave it for later.

If compression tests are bad, then check the valve adjustment.

Sputtering and coughing can be bad valves, or valves needing adjustment, it could be a bad condenser, points, or plugs/plug gaps, it could be bad fuel, old fuel, water in fuel. Until you know the difference, I would suggest starting with the simplest thing to fix first.

Well gang: Looks like I'm it. The best the old-timer could do was give me some advice. He's too backed up and needs to make money on sure-bets and faster fixes. He suggested, in addition to what all of you have pointed out, to change the condenser as well. Says that's pretty typical fix. Well, time to clean up the garage and back 'er up and get to work. Hope I can get the time to hang in there with it...got a 1 year old kiddo in the background! Wish he was old enough to put on it!

"Builder": I wrote down your sequence of advice. Thank you a ton. Agreed...i best stay away from the carb for now. That's sound advice. I've done some under the hood work as a younger guy, just haven't in 20 years and not on one this old.

Thanks Steve, and I love your website! The GMC site is a daily source of info. for me.

Well, here's what happened after work: Dumped in a can of 6-cyl.engine cleaner, dropped in some fresh fuel and some fuel cleaner....changed all the plugs proper gaping. She fired right up and drove around the block no problem! Not even a single fart, burp or bleep. I've noticed a slight leak on the manifold ports on the side of the engine. Hmm. Gasket? This is going to really sound dumb, but I don't care: There are two oil resevoirs on each side of the engine...is it cool to put oil into either side 'er what? Still learning here gang so don't beat me up too bad on this one!

Rondo:
Sounds like good news. You can try retorquing the manifold to see if that clears the leak, otherwise a new gasket is in order.

Yes, you can pour oil in either valve cover. They both let it flow through to the oil pan where the oil pickup and pump recirculate it.
Regards,
Steve
New Orleans