My 1998 Blazer timing belt may have broken?
Super Member
Joined: Sep 2010
Posts: 1,485
From: Lynnwood WA
The GM 4.3L v6 is a non-interference engine in that the valves open into reliefs cut into the pistons such that they will not contact the piston even if the valve is open to max lift with the piston at TDC. As such, if the timing chain has broken, turning the motor over will not harm anything. Now if you dropped a valve or broke a rod/wrist-pin/piston/etc, that is an entirely different story.
Senior Member
Joined: Mar 2008
Posts: 975
I have never in my 20+years as a mechanic or my 60+years alive seen a timing chain break. I have seen plastic cam gears break. With that said anything is possible. I have seen chains so loose they were slapping the timing cover. I even saw one that wore a hole through the cover on a Ford.
If the chain did break turning over the engine should be real easy. Because all your turning is the crankshaft.
I think taking it to a GOOD mechanic would be the best. I question a mechanic that doesn't know a Chevy 4.3 V-6 doesn't have a timing belt. I would even question a mechanic that thinks a chain broke. A good mechanic should not have to take much time to narrow the problem area down. So find a good mechanic they are the cheapest in the long run.
After years of working on my own stuff I'm more & more having to take my vehicles to a mechanic. Find good honest mechanic's is not all that easy. But I have been pretty lucky over the last little while. I'm all crippled up & just can't do the stuff I use to. Then I'm so far out of date with these newer vehicles that many times it is just easier to take it in.
I learn a lot on this forum & it makes me a much more aware consumer, when I need to rely on a shop.
When I can I still like to get in there & get dirty & fix stuff.
I wish you the best. Let us know what is found.
If the chain did break turning over the engine should be real easy. Because all your turning is the crankshaft.
I think taking it to a GOOD mechanic would be the best. I question a mechanic that doesn't know a Chevy 4.3 V-6 doesn't have a timing belt. I would even question a mechanic that thinks a chain broke. A good mechanic should not have to take much time to narrow the problem area down. So find a good mechanic they are the cheapest in the long run.
After years of working on my own stuff I'm more & more having to take my vehicles to a mechanic. Find good honest mechanic's is not all that easy. But I have been pretty lucky over the last little while. I'm all crippled up & just can't do the stuff I use to. Then I'm so far out of date with these newer vehicles that many times it is just easier to take it in.
I learn a lot on this forum & it makes me a much more aware consumer, when I need to rely on a shop.
When I can I still like to get in there & get dirty & fix stuff.
I wish you the best. Let us know what is found.
Starting Member
Joined: Nov 2010
Posts: 127
From: Dartmouth, NS
4.3L is considered a non interference engine, Timing chains do not normally break, I agree but also disagree.
Replaced engine in my blazer last year, took engine from a 2001 1/2 ton, Engine had 170,000K on it started and ran for 20 min, timing chain broke and bent #5 and #6 exhaust valve so yeah it can break a chain and bend valves all depends on if your luck was as bad as mine
Replaced engine in my blazer last year, took engine from a 2001 1/2 ton, Engine had 170,000K on it started and ran for 20 min, timing chain broke and bent #5 and #6 exhaust valve so yeah it can break a chain and bend valves all depends on if your luck was as bad as mine
Thread
Thread Starter
Forum
Replies
Last Post
Bonzaibob
Engine & Transmission
7
Apr 17, 2012 11:11 AM
RetroBlazer
General Chat
5
Mar 20, 2012 09:58 PM
bassman
Steering, Suspension & Drivetrain
11
May 2, 2011 04:51 PM
abig84
General Chat
1
Dec 31, 2009 05:40 PM
