6066 (1960-1966) GMC Truck Club Bitcoin now accepted here! 
Pay Dues
Pay Dues or become a Site Supporter
 



Go Back   6066 (1960-1966) GMC Truck Club > 6066 GMC Truck Club Forum > GMC V6 and V12 Engines


GMC V6 and V12 Engines Engine repair and rebuilding

Reply
 
Thread Tools
  #1  
Old February 25th, 2016, 01:12 AM
bobdylan bobdylan is offline
Senior Member
 
Join Date: Mar 2015
Location: mclouth kansas
Truck: 64 Gmc suburbann 305e, 4speed. v12 truck engine, v12 irrigation,2-305e,305a,305d
Age: 67
Posts: 373
Rep Power: 151
bobdylan is on a distinguished road
Default Removing stuck pistons

Looking for proven techniques for removing pistons, one thing taht sounds good is, after soaking with? pack cylinder with grease, put a head that valves seal tight. modify spark plug and instal grease zerk, use pressure from grease gun to shve piston out. Has anyone tried this? Bob
Reply With Quote
  #2  
Old February 25th, 2016, 05:12 PM
George Bongert George Bongert is offline
Senior Member
 
Join Date: Jan 2013
Location: Oshkosh Wisconsin
Truck: Former owner Repowered by GMC 305 V-6, 1963 Chevy 30 Series SM420 Long Bed (9') Step/Fenderside
Posts: 203
Rep Power: 129
George Bongert will become famous soon enoughGeorge Bongert will become famous soon enough
Default Re: Removing stuck pistons

Quote:
Originally Posted by bobdylan View Post
Looking for proven techniques for removing pistons, one thing taht sounds good is, after soaking with? pack cylinder with grease, put a head that valves seal tight. modify spark plug and instal grease zerk, use pressure from grease gun to shve piston out. Has anyone tried this? Bob
Greetings Bob!

I have heard of the grease gun method, although I've never tried it myself. As to soaking the cylinder(s), a friend of mine recommends a 50/50 mixture of laquer thinner and brake fluid to break the bond between the rusted cylinder and piston. Again, I never tried it myself, but he claims it works well. If you try it, let the rest of us know whether it works or not.
Reply With Quote
  #3  
Old February 25th, 2016, 05:19 PM
ilvracn's Avatar
ilvracn ilvracn is offline
-= Dues Paid =-
 
Join Date: Nov 2013
Location: atlantic iowa
Truck: 1966 gmc 1500
Age: 59
Posts: 214
Rep Power: 119
ilvracn is on a distinguished road
Default Re: Removing stuck pistons

An old mechanic once told me, water is what stuck it, so it will work the best to unstick it. I found a product called evaporust. It is water based, and it eats rust like you would not believe. It may take a few days or weeks, but i think it will work.
Website orisonmarketing.com 800-460-2403
Reply With Quote
  #4  
Old February 25th, 2016, 05:29 PM
FetchMeAPepsi's Avatar
FetchMeAPepsi FetchMeAPepsi is offline
-= Dues Paid =-
 
Join Date: Jan 2013
Location: Edmond, Ks
Truck: 1962 4x4 GMC CECILIA
Posts: 1,719
Rep Power: 507
FetchMeAPepsi will become famous soon enoughFetchMeAPepsi will become famous soon enough
Default Re: Removing stuck pistons

I don't know anything, but can you just put a block of wood on them and use a BFH to pound them out?


Maybe putting a jack under them will push them out the top?
__________________
Step by steps:

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.


To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

Some people are like slinkys. Not worth much but funny as heck when pushed down stairs.
__________________
If the women don't find you handsome, they should at least find you handy.
Reply With Quote
  #5  
Old February 26th, 2016, 04:57 PM
abus319 abus319 is offline
-= Site Supporter =-
 
Join Date: Sep 2013
Location: Austin Texas
Truck: 1960 3500, 305D heads
Posts: 116
Rep Power: 94
abus319 is on a distinguished road
Default Re: Removing stuck pistons

+1 for evaporust assuming its the rings that are stuck and your goal is to salvage the pistons.
Reply With Quote
  #6  
Old February 26th, 2016, 06:26 PM
bobdylan bobdylan is offline
Senior Member
 
Join Date: Mar 2015
Location: mclouth kansas
Truck: 64 Gmc suburbann 305e, 4speed. v12 truck engine, v12 irrigation,2-305e,305a,305d
Age: 67
Posts: 373
Rep Power: 151
bobdylan is on a distinguished road
Default Re: Removing stuck pistons

Thanks, have you tried this? Bob
Reply With Quote
  #7  
Old February 26th, 2016, 11:57 PM
ilvracn's Avatar
ilvracn ilvracn is offline
-= Dues Paid =-
 
Join Date: Nov 2013
Location: atlantic iowa
Truck: 1966 gmc 1500
Age: 59
Posts: 214
Rep Power: 119
ilvracn is on a distinguished road
Default Re: Removing stuck pistons

Haven't tried it on pistons. I have a pistol that my uncle found when plowing about 50 years ago. I think it dates back to the late 1800 era. Tried soaking it in diesel fuel for 2 years, did no good. I put the pistol in a bucket of evaporust and soaked it for a couple months. I was then able to rock the cylinder a little bit. I was pretty excited about that. So put it back in bucket, but did not get back to it for a couple months. Wheni pulled it out another chemical reaction occured, and a white powder had formed on it. Pistol stuck again. What a bummer. So dont leave evaporust in too long.
Attached Images
File Type: jpg RUSTY PISTOL 002.JPG (736.1 KB, Multiple views, 8 clicks)
Reply With Quote
  #8  
Old February 27th, 2016, 02:13 AM
bobdylan bobdylan is offline
Senior Member
 
Join Date: Mar 2015
Location: mclouth kansas
Truck: 64 Gmc suburbann 305e, 4speed. v12 truck engine, v12 irrigation,2-305e,305a,305d
Age: 67
Posts: 373
Rep Power: 151
bobdylan is on a distinguished road
Default Re: Removing stuck pistons

I think on a small part I would use electrolosis, using a bucket, battery charger some rebar. There some on youtube, I keep thinking I am going to try it, but there is the twenty unfinished projects.
Reply With Quote
  #9  
Old February 27th, 2016, 02:24 AM
GMCDAC's Avatar
GMCDAC GMCDAC is offline
Senior Member
 
Join Date: Jan 2013
Location: Green Valley, east of Rapid City,SD
Truck: I have 4 GMCs, none with a V-6 - YET! Have had 2 in the family.
Age: 67
Posts: 553
Rep Power: 208
GMCDAC is on a distinguished road
Default Re: Removing stuck pistons

Quote:
Originally Posted by bobdylan View Post
Looking for proven techniques for removing pistons, one thing taht sounds good is, after soaking with? pack cylinder with grease, put a head that valves seal tight. modify spark plug and instal grease zerk, use pressure from grease gun to shve piston out. Has anyone tried this? Bob
The grease method sounds like a pretty good idea, it sure works slick for pressed in pilot bearings. The first pic below is a couple different rust breaker sprays I've had good luck with before. I've heard kerosene and ATF mix works well but never tried it.

Quote:
Originally Posted by ilvracn View Post
Haven't tried it on pistons. I have a pistol that my uncle found when plowing about 50 years ago. I think it dates back to the late 1800 era. Tried soaking it in diesel fuel for 2 years, did no good. I put the pistol in a bucket of evaporust and soaked it for a couple months. I was then able to rock the cylinder a little bit. I was pretty excited about that. So put it back in bucket, but did not get back to it for a couple months. Wheni pulled it out another chemical reaction occured, and a white powder had formed on it. Pistol stuck again. What a bummer. So dont leave evaporust in too long.

Cool find! I wish I could remember how Mom de-rusted this pistol about 45 years ago but it came out well. I remember she soaked it in something for quite a while in our utility room and I don't remember it having a bad smell or anything. She found it while digging for old bottles at a long-gone railroad station, and it is also from around the same era.

Sorry about the brief hi-jack!

DAC
Attached Images
File Type: jpg rust 002.jpg (1.20 MB, Multiple views, 5 clicks)
File Type: jpg rust 004.jpg (1.36 MB, Multiple views, 6 clicks)
__________________
Doug Crawford
Rapid City, SD

1970 GMC K5 Jimmy Mom drove 30 years
1972 GMC C2500 owned since 1979
1955 GMC 100 driver-project
2006 GMC Yukon Denali---wife's truck

Hope to have a '60 GMC Suburban again someday
Reply With Quote
  #10  
Old February 27th, 2016, 02:44 PM
abus319 abus319 is offline
-= Site Supporter =-
 
Join Date: Sep 2013
Location: Austin Texas
Truck: 1960 3500, 305D heads
Posts: 116
Rep Power: 94
abus319 is on a distinguished road
Default Re: Removing stuck pistons

I haven't tried the evaporust on a stuck piston yet. My thoughts were that eliminating the rust bond between the rings and the cylinder wall with a non damaging product like evaporust might be a better first step than applying force.
I know these pistons are stout but i would be concerned about breaking or deforming a ring land with the grease gun method.
On my 478 I used a mix of trans fluid and diesel in the cal, and built a torque plate to attach an impact to the end of the crank. Two or three second burst, reversing each time, several times a day broke it loose.
Do you have the heads off, or is this one of the engines that was stored without the heads? if so how do they look?

Last edited by abus319; February 27th, 2016 at 04:35 PM.
Reply With Quote
Reply

Bookmarks

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Stuck clutch 62 4 speed Ancientx Transmissions and Rear Ends 2 July 3rd, 2015 04:57 AM
stuck 478 abus319 GMC V6 and V12 Engines 56 May 14th, 2015 04:53 AM
Stuck spark plug jagarra GMC V6 and V12 Engines 27 December 6th, 2014 10:25 PM
Rear Drum Stuck adjuster frozen Schroer1962v3000Dump Wheels, Tires, Suspension and Brakes 2 May 8th, 2014 01:12 AM
Stuck 'em Archiver Previous Forum Posts 0 October 11th, 2002 02:36 AM


All times are GMT +1. The time now is 02:32 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2013, Jelsoft Enterprises Ltd 611708799351|1707615157|0
Feedback Buttons provided by Advanced Post Thanks / Like (Lite) - vBulletin Mods & Addons Copyright © 2024 DragonByte Technologies Ltd.