GM 366 engine

[Tucker943]

Any tips? Lots of tree trucks out there have them? Best oil weight? Any minor mods to step up power a bit?

 

[Al Smith]

I think a 366 is an industrial version of a 427 .They have enough pulling power without doing anything to them as I recall .It is to GMC what a Ford 371 was ,tough azzed engine .

 

[Tucker943]

Ya, the only thing I know is you have to wind em up real high to get the power up. If You keep the RPM's up, they'll earn their keep.

 

[Al Smith]

You get on truck forums some swear by them and some swear at them .I think it's just personal preference.Then again some are under the opinion a ton a half truck should be a hot rod which it isn't .

When Ford built the big block series the 370 or 371 was used in fleet trucks like Ryder rentals etc .It had enough grunt but wasn't as robust as the 429 industrial with a steel crank and forged pistons,hard insert valve seats which was used on cement trucks believe it or not .The 460 for truck application was used on medium duty trucks .

I suppose GMC probabley did about the same .Big gassers are almost a thing of the past .

 

[lumberjack]

My experience with them is the power sucks, fuel mileage sucks, they are old and getting older, and they don't die with any regularity. A manual is preferable to an automatic.


I'm well happy I made the switch to diesel.

 

[Al Smith]

Oh while I'm thinking about it I just thought of something .Last summer I ran Tom over to south of Ft Wayne Ind .to retrieve his bucket truck that was being recertified .That shop had a late model GMC elevated bucket with a fuel injected 454 in it .

As a rule most would have had a diesel engine but that one was a big orange truck built to spec.Which is typical of the previous company that owned it .

 

[Tucker943]

Carl, I prefer diesel myself. I bought a truck with a 366 in it for next to nothing last year. I wasn't actively searching and wanting a gasser, but I saw an opportunity to grab something up with enough wiggle room to turn a profit on it if I decided it wasn't well suited for my needs.

 

[HolmenTree]

I had a 1965 Mercury 800 once [yes a Mercury 800] she had a 391, double pumper Holley with governor, 5 speed and split rear single axle. Would only do 60 mph and burned about 4 mpg, but was a tough old girl and wouldn't die. I could carry 3 cords of green birch on the back of her.
A buddy of mine has a nice older early '70s GMC 8500? tandem picker truck with a 427 runs really nice, he says he wishes he had a diesel but he says he's happy with what he has seeing it has been paid for many years ago. Chevy made a truck engine close to 500 cubes if not over which a lot of hot rodders still look for.

 

[Tucker943]

Nothing wrong with gas. Diesel is a plus, but gassers pulled in a lot of revenue in the various trades since trucks were on the road. There's valid points to be made on both sides. Diesels last longer and work more efficiently, but some diesel repairs cost as much as replacing a gas engine entirely. I prefer diesel myself. I seem to get more work per gallon whether we are talking truck, chipper, etc..

 

[woodworkingboy]

Speaking of diesels, I was riding an excavator all day yesterday digging holes to bury brush, one not belonging to me, and the only one working at the site. Fuel gauge was on E when I got there, and it kept running for half a day, then ran out of fuel. I put ten gallons in and it was very hard starting. It would kick over and run for a few seconds, then die. After about ten-fifteen tries, it finally kept going. My old diesel truck, when it ran out of fuel, you had to put some fuel in another location in the engine besides the tank to get it started. Nobody to ask, so I just assumed since the mini is a much later machine, it wasn't required to do that, probably an obsolete procedure to put diesel elsewhere first nowadays. Just wondering, is that typical that when you run out of diesel, the engine is difficult starting and running properly? Maybe there is something else to aid starting, like with the throttle....going back and forth from low to higher rpms seemed to get the fuel moving finally, or whatever the deal was? Thanks.

 

[Tucker943]

Somewhere on that machine yesterday was a primer to bleed the system. That or you open injector lines and crank it to bleed the system and get fuel to the injectors. Getting it restarted by cranking on it over and over is possible, but easily burns up the starter. Ive seen guys get the air out in a variety of ways, including running the engine on ether until it takes off on diesel. That monkey business is lunacy. Best way next time Jay, is to find a small pump/bleeder, often somewhere along the engine block, and pump away at it until you get a feeling of resistance. That or open the injector line on the farthest injector from the injector pump and crank it until fuel sprays out and close the line back up. Can be tough to do alone.

 

[woodworkingboy]

Gotcha, thanks very much, Chris. Now at least i know that there is something proper to be done.

 

[Burnham]

Even with new diesels...NEVER run them out of fuel. I'm surprised you were able to get it to restart at all, without going through the whole re-prime procedure.

 

[woodworkingboy]

It was a race to get it started before the battery lost it's juice, thought I might have to go home. I should admit to a little perverse curiosity, half wondering what is going to happen when it runs out. A few days earlier when I mentioned something to the owner of the machine about running out of fuel, he didn't seem much concerned, so I wasn't so much either, figured it wasn't so problematical. In retrospect, he is a hard worker, but also the type that often doesn't seem very concerned about much of anything, and often to his credit. Guess i was lucky, not getting it running would have seriously messed up my plans. Yay for Kubota!

 

[Burnham]