The 1947 - Present Chevrolet & GMC Truck Message Board Network - View Single Post - 1967 GMC V6

Blue Sage · 07-01-2019, 01:35 PM

Hi GMC and Chevy Truckers,

I'm brand new to the site and am hoping for some guidance and info on rebuilding a 351E. I bought the truck with the original Camper Queen camper on it - which were bought together in '67 by a military man who kept extensive maintainance records and receipts. The engine was completely rebuilt in 1998 and various things added - power steering, dual battery charger and AC.

WHen I got it in 2006, it had the wrong carburator on it and only got 5 MPG. In the process of putting on a different - used - carburator - a 1/4 inch bolt fell in the spark plug hole for which I will surely go to mechanic's hell for a few seasons. The bolt banged up against the head about 20 times before I just abandoned the truck in my driveway that Autumn thinking I'd thrown a rod. In Spring I took the corresponding head off the V6 and found the bolt had bounced around the head a few times and settled next to the cylinder wall scoring it but just barely. A diesel mechanic told me that because the score is above the rings it will fill in with carbon and all will be well. Right?

So, my job initially is to put it all together again and then start from the beginning to analyze the engine for 1. leaking cylinders and 2. leaking rod bores and 3. out of round journals on the crank shaft.

I realize that because the piston cracked up against the head (away from the valves) that despite there being no visible cracks under the bolt, it still could have micro cracks that could ultimately break up the piston so that that piston should be replaced with new rings and bearings on the journal. But my logic is that the piston could withstand going back into the cylinder for a brief period so as to test the entire engine for efficiency, then take it apart again and replace the piston with new rings. Sound doable?

On the other hand, I could buy a new piston, rings and bearings (where would I find such things please?) and THEN test the engine in the event the engine is OK, and then I wouldn't have to do it over again. I have some mechanical skill having done a Dodge slant six rebuild in '84 that still runs!

Any help I can get on this deeply appreciated. I'd love to the that Camper Queen on the road again! Thanks, Blue Sage

07-01-2019, 01:35 PM	#1
Blue Sage Registered User Join Date: Jun 2019 Location: Taos, New Mexico Posts: 22	1967 GMC V6 - 351E on a Camper Cruiser Hi GMC and Chevy Truckers, I'm brand new to the site and am hoping for some guidance and info on rebuilding a 351E. I bought the truck with the original Camper Queen camper on it - which were bought together in '67 by a military man who kept extensive maintainance records and receipts. The engine was completely rebuilt in 1998 and various things added - power steering, dual battery charger and AC. WHen I got it in 2006, it had the wrong carburator on it and only got 5 MPG. In the process of putting on a different - used - carburator - a 1/4 inch bolt fell in the spark plug hole for which I will surely go to mechanic's hell for a few seasons. The bolt banged up against the head about 20 times before I just abandoned the truck in my driveway that Autumn thinking I'd thrown a rod. In Spring I took the corresponding head off the V6 and found the bolt had bounced around the head a few times and settled next to the cylinder wall scoring it but just barely. A diesel mechanic told me that because the score is above the rings it will fill in with carbon and all will be well. Right? So, my job initially is to put it all together again and then start from the beginning to analyze the engine for 1. leaking cylinders and 2. leaking rod bores and 3. out of round journals on the crank shaft. I realize that because the piston cracked up against the head (away from the valves) that despite there being no visible cracks under the bolt, it still could have micro cracks that could ultimately break up the piston so that that piston should be replaced with new rings and bearings on the journal. But my logic is that the piston could withstand going back into the cylinder for a brief period so as to test the entire engine for efficiency, then take it apart again and replace the piston with new rings. Sound doable? On the other hand, I could buy a new piston, rings and bearings (where would I find such things please?) and THEN test the engine in the event the engine is OK, and then I wouldn't have to do it over again. I have some mechanical skill having done a Dodge slant six rebuild in '84 that still runs! Any help I can get on this deeply appreciated. I'd love to the that Camper Queen on the road again! Thanks, Blue Sage