292 Questions

[May70]

I blew out the line from the sending unit up to the fuel pump. I got a tiny spec or two and that was it. Sprayed about a half bottle of carb cleaner down it and blew it out for a good minute. Seems clean and clear for the most part. Decided to take the sending unit out of the tank to see how that sock was looking (see pic). The sock really didnt look bad but the tank is rough. I siphoned out a little less than 5 gallons which seemed to be almost all of it. I ran it all through a t shirt to transfer it and you can see in the pic what 5 gallons worth held. Guess this marks off the theory that the something was plugged up but gunna need to take care of this tank now and hope the new fuel pump does the trick.

I have read some shops offer services to bath these in something and clean them up. Not real certain anyone close to me does that. Ill have to check around and on the price. A repo tank is 200 shipped from lmc but I think I could do better cleaning it myself and sealing it. That red kote stuff I have seen mentioned several times.

Ive got a jar of BBs that I think I might shake around in there to start with, nuts and bolts. Suggestions are welcomed, ha ha.

[RichardJ]

The only way you know for sure if your head uses tapered plugs or the gasket plugs is to look at the plug hole.

On a 50 year old engine, your head could be from a 230, a 250 or a 292. It could be from an earlier engine with gasket plugs or the later style. If you insist it's an all original, unmolested engine, you're a dreamer.

[Motorfist]

I've messed around with a lot of classic motorcycles over the years and have seen some coatings fail that were done by professionals. I will never use one again personally. Next time I run in to an issue I plan to try this stuff https://www.workshophero.com/products/metal-rescue/

If you're not interested in something like that, my advice would be to get as much of the loose crud out of there as possible and be diligent on replacing fuel filters. Avoid ethanol gas if possible and if not possible, never let the truck sit for extended periods of time without a full tank.

Or bite the bullet and replace the tank.

[May70]

Originally Posted by Motorfist

I've messed around with a lot of classic motorcycles over the years and have seen some coatings fail that were done by professionals. I will never use one again personally. Next time I run in to an issue I plan to try this stuff https://www.workshophero.com/products/metal-rescue/

If you're not interested in something like that, my advice would be to get as much of the loose crud out of there as possible and be diligent on replacing fuel filters. Avoid ethanol gas if possible and if not possible, never let the truck sit for extended periods of time without a full tank.

Or bite the bullet and replace the tank.

Even with that what are you going to put on the metal to keep the rust from coming back? Im planning on picking up about 10 gallons of vinegar to put in there, doing a lot of shaking and sitting over at least a few days. Then maybe coming back with evaporust or that metal rescue stuff depending on how bad it is after the vinegar. Im still thinking that after that I will need to put some sort of seal/coating to prevent it from rusting back quickly.

[Motorfist]

I personally would not put vinegar in there. It will loosen the rust which will need wiped off somehow and then the tank will be coated in a thin layer of rust again. I have been through that with bike parts. The acid in it will create flash rust because the acid etches the metal.

I have no affiliation with the Metal Rescue stuff and dont know if it works as well as they claim. But if it works even half as good as they claim, it should be awesome. They even compare it to vinegar on their website.

Supposedly, it doesn't create flash rust. To avoid rust build up again, I would defer to my statement about avoiding ethanol and also avoiding storing the truck without a full tank of (preferably treated) fuel.

My hang up with doing your gas tank with Metal Rescue is the cost. I bet you'd need to spend $150 on the stuff to effectively clean your tank. They claim it is reusable so unless you have other projects to use it on, it's not worth it.

I did a site search for Metal Rescue and it looks like other folks have used it with success. And you can buy it at Home Depot

[Steeveedee]

Do you have access to a feed store? You can buy and dissolve some powdered molasses for way cheap and it will take the rust off, just like Evapo-Rust does. You will still have to seal the metal some way, though. I have yet to look back through you thread here. I've been slackin'.

[Mike_The_Grad]

Mav70, the issues you're running into remind me of what I'm going through with my dads truck. 64 c10 LWB 292 4 speed granny low. His gas tank looked like something out of cave diving documentary. Stuff growing out of the sides and bottom, yellow, varnished, nasty stuff. We had a spare gas tank we got in a craigslist purchase of a different 292. That block turned out to be cracked, but we got a lot of parts. Well the tank they gave us was practically spotless inside. Save for some "white rust" (yes, it's a thing google it.) Not wanting to risk clogging up the new sending unit sock I wanted to clean out the tank somehow. Here's the best advice I could glean from YouTube and the internet:theres quite a few different methods for cleaning a tank. Best solution obviously is to replace the tank and sending unit. If that's not in your budget then you have to get the bad stuff out and ideally prevent it from coming back also, neutralizing whatever method you decide on to prevent further damage. Being that the tank we have only had some white powdery stuff inside I didnt want to get to aggressive with it. Some type of media would be best for heavy sludge/rust/junk. Like:Nuts,Chain,BB's,Pea gravel, etc. What you want to ensure is that whatever you put in, comes back out. So count all of the pieces of whatever you use to ensure they are all accounted for when you dump them out. I ultimately went with apple cider vinegar for cleaning my tank. Picked up a gallon at the local supermarket for about $5. Dont get the organic stuff costs almost 4 times as much. I poured in about a half gallon and gave it a good shaking and swishing around. Then I played it on each different side as best I could for a few hours each. Then poured out the liquid. It looked ok maybe a little tinted. Then I washed it out with the garden hose. Then heated a gallon of distilled water on the stove in a big pot to almost boiling and added about half a box of baking soda and stirred it real good. Then poured that in about a quart at a time and shook it all around in the tank. Emptying the tank each time. One last rinse with a gallon of distilled water from the jug and put my air nozzle inside till it looked dry. Sealed it back up until I was ready to install it in the truck. When I unsealed it, it was still dry, no rust and no more white stuff.

['68OrangeSunshine]

I've had good results [twice] from removing the tank completely and taking it to a good radiator shop, and having them hot tank it or steam-clean it. Once with the 22.5 gallon in-cab tank on my Stepside, and once with a 20.5 gallon belly tank from my '67 Suburban.
Some of these shadetree methods scare me. Molasses, really?! Don't vandals sabotage an enemy's engine by putting sugar in the gas tank?

[Steeveedee]

That's a myth. Sugar doesn't dissolve in gasoline. Molasses works, and of course if he used it, he'd flush it out afterwards.

[Mike_The_Grad]

Interestingly enough, my post about the spark plug type for these engines seems to be partially correct. I have 3 cylinder heads from different engines. 2 of them take the gasketed type of plugs while the other one I have(which is on the 292 I'm putting into my dads truck coincidentally) takes the taper seat plugs. Richardj was spot on with his post. When I screwed in the gasket plugs lastnight, my 13/16" socket wouldn't even fit into the cylinder head pocket where the plug goes. Like I said, it dont mean that they all take the gasket type but they usually do. If a 13/16" socket dont fit, then the head obviously doesn't take the gasket type of plug.

Any updates?

[straight6chevyguy]

Originally Posted by May70

Anyone got a number? Parts store has the 292 coming up as having the tapered plugs. When I go to summit I see both listed for a 292. I will do some research on the side if no one has that info off the top.

I am currently using NGK 4922's in my 292.

['68OrangeSunshine]

I used to use AC Delco R44XLS in my 292. A vintage L6 head uses plugs with a 13/16'' hexhead. I have a 1998 crate Mr Goodwrench 350 V8 in my '71 GMC Jimmy. The plugs in that require a 5/8'' socket.
I use Denso 3021's now, since AC Delco went to Mexico.
HEI Gap .045
Points Gap .035

[Mike_The_Grad]

Autolite 404 for the gasket type.
ACdelco R44ts for the taper seat type.

[straight6chevyguy]

Please forgive me if I just over looked it but I don't believe that you ever said what year your truck was?

And do you know what year your engine is? (If not original)

[Mike_The_Grad]

Not to hijack or anything. A question about carb base gaskets. It may help out may70 and myself. Which ones are you guys with a single barrel carb running? I bought a carb rebuild kit some months ago from Carbs unlimited and it came with several different styles. All of them fit the base plate of the rochester model R1-BV. With the only differences being that 1 gasket covers the entire base of the base plate, another leaves 2 ports located in the base plate uncovered and with channels cut into the gasket exposed to manifold pressure. And the other is the same with channels exposing the same 2 ports but has more channels evenly spaced around the inside diameter of the gasket. My carb only has 2 ports in the base plate flange, but am unsure if they need to be exposed to manifold pressure or not. This may be something that is causing may70 some issues also if he doesnt have the correct base gasket for his setup. I dont have a point of reference to check against because my setup was Mickey Moused together by the P.O. (the float bowl had no gasket and the linkage involved some type of Rube Goldberg contraption.)
If the replies are a little involved or begin taking the thread in a different direction other than helping out the original poster, I will start my own thread or take PM's. Thanks in advance.

[May70]

I called around none of the shops here are doing gas tanks anymore. One shop said he had one done a couple months ago and the closest place was in MD, and they cut the tank open, blast, coat and weld back ($$$$$$$$$). Soooo, ive had 10 gallons of Walmart's finest white vinegar sitting in this tank for maybe 5 days ish. Cost me $25. Its working wonders. I poured it out and filtered it, then put it back in. There was no residue left just mostly clean metal, I rinsed it out good so maybe that was the difference. I ran the chain through only a few times. Once I get it pretty well cleaned up with the vinegar Im not going to empty it until I am ready to start what ever sealing kit I buy.

The truck is a 1970 c20. I have no reason to believe this isnt the original 292 motor, i haven't looked at the vin on it yet so I dont know for sure. I dont know if its had any major work done to it. Honestly the PO(s) neglected this thing pretty bad, its been leaking for a loooooong time, so I would be surprised if he paid for major work to be done. The rockers/cab corners they did put on were a shabby job, looks like a street sign in part of the floor pan. Not saying I know one way or another. I dont know if this is the original head etc.

Once I get all this fuel/carb situation straightened out and it runs decent the head is coming off and im doing valve seals. I am really hoping this bogging out problem is an issue with fuel delivery. With the tank cleaned out, new rubber lines, metal lines blown out and a new fuel pump... I think ill find out pretty quick.

I think I only saw one reply, Mike, about the carb gasket and that was basically that I probably only needed the thick gasket. The kit I ordered is specifically for the monojet so not sure why multiple options on manifold-throttle body gasket. I guess its a just in case type deal but it would be nice to know.

Ive been looking at 2 part systems to coat the tank and single stage products. There is a never ending discussion with which is best I know but a two part theoretically will out perform a single stage in almost any situation. Caswell's sealer looks good, I have not found any bad reviews on and it says its an option to fix failed kreem or por15 jobs. They want 100$ for the 20gal tank kit..too much for me probably.. Haven't decided on which coating yet. Even if you don't use an etching product its going to rust back with bare metal, if the rust was there once, any coating from the factory is long gone. I did look at metal rescue but doesn't coat it, it leaves bare metal and in the description it says 'ready for use or additional processing' which means ready for coating of some sort. That's basically where im at now. For all of these reasons I would definitely elect to coat it or buy new, just in general. Im not going to buy new at this point because when I do start a full blown restore I will hopefully be moving the tank out of the cab. Now I am not ready to do that and don't want to drop $200 on a tank im not keeping. Ive watched several youtubes where a quart could have done two or more 20 gallon tanks with the por15 stuff.

I haven't done much in the way of installing new fuel pump or checking which plugs I should be using. Had some health issues going on and have been trying to get my 62 runabout 100% complete. Hopefully ill get the fuel system back in within a few more days.

Thanks for all the feed back and stickin with me. Much appreciated and I am surprised with how much I am learning. No wonder they call it a labor of love. Its cool to see so many people helpin others out online!!

['68OrangeSunshine]

Your engine number won't be related to the VIN. Truck engines did not get the body VIN stamped on them because with a truck, the engine was considered a replaceable item.
On L6 blocks, an ''engine dress number'' was stamped on a machined pad behind the distributor shaft hole. You can deduce the plant, build date, and original application frome these numbers and letters.
Example: F0626UH = Flint MI, June 26th, 292 w/manual xmsn -- 67-68.
Decoding lists are online or even in the LMC catalog.

I guess it was 20 years ago I had a 1967 cab tank cleaned out to replace my original '68 tank. The newer gasoline formulation was dissolving 30 years' worth of gunk from the bottom, clogging the carb -- and the twist-lock of the neck was chewed up from having lost the key to a locking gas cap. I guess you can't get it done anymore.

[May70]

Rinsed vinegar out good. Put about a quart of purple power and filled the tank to the brim, sloshing it around while it filled up. Let that sit for about 20 minutes then rinsed it out very well again. I hooked up an electric blower and let that run for about an hour through it. Then took some acetone and sloshed it around two times. Let the tank sit and get 100% dry for about 24 hrs. A little surface rust came back over night, but the product I bought is made for heavily rusted surfaces and to seal up pin hole leaks. So I had no second thoughts. Ended up going with red kote, Oriellys had it in stock. Looks pretty solid. Just finished draining the tank of the extra a little while ago. Pic i took was right after I drained it and everything got great coverage. Not perfect but im hoping it will get er done. I used just about a quart, maybe a tad more. Clean up wasnt bad with acetone. Definitely a work out though ill tell ya that much. Slowly rotated the tank for 15 minutes. Key with this red kote (so i read) was to make sure the tank was dry before hand and give this stuff plenty of time to dry before putting gas in it. I will probably give it two weeks before putting any gas in it to make absolutely sure its good to go. Im hoping those runs from draining it level out a bit, can says they will. If not o well.


Put the new fuel pump on, new lines and cleaned out the metal lines. I still want to trouble shoot why my gas gauge isnt working while Ive got all this going on. Found a good thread on that here. Read its somewhat common the resister on the back of the gauge goes out...

When I took the seat out the floor pan was looking rough. I ended up wire brushing the whole back side and then using some rust converter on it then primed. Should just keep things over till im ready for the dirty work

Picked up a hobart 210, going to run the plug tonight from my sub panel. This thing is sweet. Can't believe I actually have one. Went with an 80cf bottle. Ended up buying it cause the local shop doesn't lease. $200 for the tank, 40 for the fill. When its empty I just trade it in for another filled one for about the same ~$40. Ive used a flux core a few times doing very crude, stick two things together, and it was baaaad. haha should be a good time...

[Mike_The_Grad]

Good stuff may70. Glad to to hear an update. I'd like to know how that Hobart works out for ya. Having a dedicated circuit is a must with any welder. A buddy of mine kept wondering why his garage breaker would trip everytime we used the welder...lol.
The sending unit issue could be one or two of only a few things depending on what it is you're experiencing. If your fuel gauge reading is way past full towards about the 3o'clock position, more than likely it's your sending unit that's bad. If the fuel gauge is reading lower than what you think it should be, more than likely it's your float. They can leak just like some of the carb ones. And my experience with aftermarket floats that are included with the sending units available from pretty much any vendor is that they are junk. Assembled over seas where apparently there is a shortage of solder because the last 3 brass sending unit floats I got were all junk from a pinhole in the solder joint. I ended up switching to a plastic float for my 72 c10. They dont have the same issues as the brass ones. And they fit the sending unit arm perfectly. Cost about $5 too. If your interested try finding a sending unit float for a 1975 jeep cj5 I think it is. Someone will verify I'm sure or try a search for plastic sending unit float up in the search bar.
The only downside I could talk of is that when I top off my tank it sounds like theres a pingpong ball inside the tank. But only for the first few miles. After that not even a thought.

[May70]

My fuel gauge is always at the same spot. The gauge reads around half a tank I think, definitely not past full. I also read of people coating their float in this red kote stuff. After all it is intended to seal holes etc haha. Just a thought if that turns out to be the problem. Maybe I should give it a dip anyway.... Have to do some trouble shooting with the help of this post

http://67-72chevytrucks.com/vboard/s...d.php?t=640615

Anyways yes I ran a dedicated circuit. #8 wire to a nema 6-50 with a 40 amp breaker. Max pull on this thing is 35 amps. I will probably never use that but better to do it right from the get go.

Will check in when I get some forward progress. Just ordered a filler neck grommet from Wes. The old one was super rotted and a pain to get off. Whats the best way to install those? Put it on the filler neck then push it out through the hole or put the tank in and then the grommet on from the outside? Hopefully this new one is a bit more flexible

[Mike_The_Grad]

On my 72 c10 i put the grommet in the hole on the cab from the outside first. Then i guided the filler neck through it when i reinstalled the tank. Use silicone spray on both the neck and grommet. I'm sure almost any type of spray lube would work, but i like the silicone spray by itself because it doesnt mess up paint or smell too bad generally. I think there are 2 different grommets used for the 67-72 trucks. I wasnt sure which one mine took when I ordered mine, so I ordered both. One was obviously wrong when compared to what I had. Something you may want to consider since you have the tank out is to coat the outside of the tank and/or the cab area where the tank mounts with some type of sound deadener or coating. I wish I would have sprayed the outside of my tank and the area behind it while it was out with what I ended up using on my floor pan and inside my door shells. I used duplicolor rubberized coating and sound deadener. I used a full can inside each door shell and I think 3 cans on the inside floor pan. Made a huge difference in the interior sound level, and the doors sound more solid when they're shut. It did smell a little of asphalt or petroleum-ish for a couple of days but I just rolled the windows down and eventually it went away for good. I did do the fuel tank in my dads 64 c10 that I'm currently working on and is why I wish I had done my own in my truck.

[Steeveedee]

OK, I went back through this thread. The only thing that jumps out at me is that the fuel sock looks like it is collapsed, to me. That doesn't change the off-idle stumble, but it does give a problem at speed, which you mentioned when you were going 55 or so and it started in surging, but you could drive it at 35 OK.

[May70]

Originally Posted by Steeveedee

OK, I went back through this thread. The only thing that jumps out at me is that the fuel sock looks like it is collapsed, to me. That doesn't change the off-idle stumble, but it does give a problem at speed, which you mentioned when you were going 55 or so and it started in surging, but you could drive it at 35 OK.

This is a side view of the sock. I can push the sock together pretty easy but im not sure how stiff its supposed to be. It looks similar to pictures I see of new ones. It doesn't look bad to me but i would trust experience vs my judgement.

If you think this one is gone, I can replace. I see i can order just the sock online, how do you attach it to the tube? Does it just crimp itself on the tube when you push it on? Mine seems to be on there pretty good. It looks like a few little dabs of adhesive are on it.

[Steeveedee]

Looks like it is crimped at the base. I've not replaced any, only the whole sending unit. If it seems pliable, and doesn't appear clogged in the holes of the mesh, it's probably OK. Then again, that last amount of gas in the tank was enough that it should have continued to flow when you took the suction line off the fuel pump. If it were mine, I'd replace it.

[RichardJ]

That sock looks near brand new. You're grasping at straws.