replacing pistons only

[flyboy1100]

so maybe not the proper way to do it. but i have 2 pistons with broken skirts on my wee-oh-five. can i just replace those pistons with the engine still in the truck, or do i need to pull it? it just changes where i have to do the work because i don't have an engine stand or a picker.

can i still drive the truck as is? i have no idea how long the pistons have been broke anyway. i just want to keep the engine running while i try to source a new powerplant.

i suppose i could buy a rebuild kit and a cam to get a little more out of the wee-h-five too. but if i am going to rebuid anything it might as well be a 350 that is currently in good running order

and this would be a good excuse to find a new engine, and i haven't checked yards yet, but up here it seems like finding a 350 is not that easy or they want way too much money. and not sure i really want to dump 2500+ into a GM 350/290hp for this truck because i don't plan to fix the body.

sorry i'm rambling.....

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[Georgeb]

Some will say yes and some will say no. I would say yes if it you plan to replace the motor at some point in the future. If you drive it the way it is you risk the rest of the skirt breaking off causing the piston to **** and contact the head. been there and did a full rebuild. It can be done with the head and the pan removed while in the truck but you will need to have a shop press the pin out of the rod and install the new piston. Budget would be my deciding factor.

 

[flyboy1100]

What about just slapping in a full rebuild kit with no machine work? Truck is only driven about 7k/yr

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[MikeB]

Sure, but remove the heads and pistons first to see what the cylinders look like.

Also, the biggest cam I would go with in an otherwise stock 305 and stock geared truck would be something similar to a factory 350 cam from that era. Otherwise, the 305 will turn into a dog at low-mid RPMs.

I just noticed your truck is an 86 model. Do you know if it has a roller cam? 86 1/2 ton trucks with 350s did.

 

[flyboy1100]

No idea. Other than pulling it apart is there anyway to find out?

Stock 3.42 gears with 30.5" tires (265/75r15) so it is already a bit of a dog. Could be the combo or just the 305.

And would i assume to just get a standard rebuild kit? I have no idea how to mic anything anyway.... Never torn this deep into as motor, always wanted too just never have



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[Georgeb]

What about just slapping in a full rebuild kit with no machine work? Truck is only driven about 7k/yr

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You will need to cut the ridge out of the chlinders and at the very least break the glaze so new rings will seat. Of course you will need to measure the culinders to determine the correct size ring

 

[Jrgunn5150]

If you need to do it to get by, go ahead. It might last a long time, who know's lol.

If it's to get by, I would do the bare minimum. Honestly, for not alot more that what you're looking at, you could swap in a running 350. I see them for around 200-350 pretty regularly.

 

[flyboy1100]

If you need to do it to get by, go ahead. It might last a long time, who know's lol.

If it's to get by, I would do the bare minimum. Honestly, for not alot more that what you're looking at, you could swap in a running 350. I see them for around 200-350 pretty regularly.

need to find one....been looking. probably not in the right place, ha!

 

[Jrgunn5150]

car-part.com is a good start, various Facebook groups are always good for a deal once in awhile, in between all the nonsense.

 

[flyboy1100]

there is only 1 of my local yards on car-part. the rest i need to actually call. i plan to this week.

any idea which Vin i would need if it is L or M?

The other thing is i have no idea how long the piston skirts have been broken, could have happened last week or before i bought the truck 13,000 miles ago. I am inclined to think it was not a recent event. Will check the bottom a little more thoroughly in the morning

 

[Jrgunn5150]

there is only 1 of my local yards on car-part. the rest i need to actually call. i plan to this week.

any idea which Vin i would need if it is L or M?

The other thing is i have no idea how long the piston skirts have been broken, could have happened last week or before i bought the truck 13,000 miles ago. I am inclined to think it was not a recent event. Will check the bottom a little more thoroughly in the morning

Sorry, I can't help with the VIN, but anything up to 95 can be made to work pretty easily. The worst would be if it didn't have the fuel pump pushrod hole cast into the block, then you'd need an electric fuel pump, but still not a huge deal, and easier than changing pistons lol.

You're probably right, it's probably been running that way forever, and if it's not getting any worse, I'd let it go while I saved all my little ducket's for a decent motor.

 

[flyboy1100]

So up to 95 still has the hole for a fuel pump?

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[flyboy1100]

It seems that is correct anyway, or it can be drilled bit that is a hassle i don't want.

I know an olds 350 won't bolt up without an adapter. But what about a Buick roadmaster engine or similar?

Can i reuse my intake and carb? Carb might need new jets i would assume

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[jetman]

Keep your eyes open for a rusty, banged up truck with a decent 350. Last month I picked up a 1986 K20, plucked a 350 "M" with 175# compression & 40# oil pressure, no smoke, oil leaks, knocks or blow by. Paid $700 for the whole truck, sold all the parts for $1200, put the 350 (radiator thru flywheel) and AC system in the barn.

 

[flyboy1100]

Keep your eyes open for a rusty, banged up truck with a decent 350. Last month I picked up a 1986 K20, plucked a 350 "M" with 175# compression & 40# oil pressure, no smoke, oil leaks, knocks or blow by. Paid $700 for the whole truck, sold all the parts for $1200, put the 350 (radiator thru flywheel) and AC system in the barn.

been looking. there is one for 800 somewhere around me i think. need to look again