Life a Chevy 4.3 V-6 Can Run?

   / Life a Chevy 4.3 V-6 Can Run? #1  

Gale Hawkins

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Sep 20, 2009
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Location
Murray, KY
Tractor
1948 Allis Chambers Model B 1976 265 MF / 1983 JD 310B Backhoe / 1966 Ford 3000 Diesel / 1980 3600 Diesel
Looked at a 1998 S-10 5-speed Chevy PU with 524K miles on it today that is not to use over a quart of oil between 3K oil changes and I know it sounds as good as our 2002 4.3 auto in our Blazer with 192K mile and it seems to have more power but it could be the auto vs. manual factor. It shifts like new which does not make sense. The seller worked for the past owner and has personally put the last 300K miles on the truck himself providing escort service for new mobiles homes over east/central US for years.

He stated the engine has had NO work done internally but most all moving parts that bolt onto the engine as been replaced with some being replaced several times. It got a new intake gasket about 100K miles ago and has been running the old green type antifreeze for years.

Inside and out it is almost a mirror image of our 2002 Blazer but rougher for the wear of the extra 330K miles/four years.
 
   / Life a Chevy 4.3 V-6 Can Run? #2  
Those 4.3l V6's were great engines. It was the same layout (bore x stroke) as the all mighty 350 small block and just about every part from bearings to pistons and valvetrain parts are completely interchangeable. So basically it was the V8 350 with two cylinders chopped off.

I have a feeling you wont see any more 300k+ miles engines nowadays.
 
   / Life a Chevy 4.3 V-6 Can Run? #3  
The 4.3 is cast iron engine and heads, with the only weak spot the aluminum intake and the plastic gaskets G.M. used for a few years. The gaskets crack over time, and leak coolant into the oil....usually right behind the alternator on the passenger side. The new fix was to replace the plastic gaskets with metal ones....just like they used before someone had the bright idea to start using plastic gaskets. Great motor.
 
   / Life a Chevy 4.3 V-6 Can Run? #4  
What are the best years to look for? I have a V6 Toyota truck that needs a transplant, and the 4.3 is an easy swap.
 
   / Life a Chevy 4.3 V-6 Can Run? #5  
What are the best years to look for? I have a V6 Toyota truck that needs a transplant, and the 4.3 is an easy swap.

I don't know when they switched from throttle body to fuel injection, but my 2001 ZR2 is fuel injected. Sometime in the mid 2000's they switched back to the metal intake gaskets. I like the fuel injected ones, and you can always swap out the intake gaskets before you install it. Good luck.... Jerry :)
 
   / Life a Chevy 4.3 V-6 Can Run? #6  
I still wouldnt want to pay too much for a 500k mile vehicle. I hope you get it cheap.
 
   / Life a Chevy 4.3 V-6 Can Run?
  • Thread Starter
#7  
Well I liked the way it drove and it did not seem to need anything like brakes, tires, transmission (manual with firm clutch) so I went ahead and picked it up for $1100 even though the 98 S10 4.3L is showing 524K miles as a project truck.

It is so much like the 2002 Blazer and I have the factory manuals for it which should be good info for a lot of the same systems in the 1998 S10.

The truck had not been driven in a month the guy said but I would guess it could have been several months because it was parked in a shed over at his mom's place.

Coming home in it I noticed it would miss if I got on it hard running down the road like going from 30 to 50 mph in 3rd gear (still under 3K RPM) and it would keep missing for maybe a half mile then smooth out again.

After driving it about 60 miles in 20 mile runs me and my son hooked the scanner to it and drove it some. The miss would return then go away. Then I got on it harder (no red lining stuff but more like some take offs like the 2002 Blazer does over and over without issue we got it to pop PO305 that then turned into a PO300 multi cylinder miss that no longer goes away. The MAF PO101 over time will reset after cleared.

Well the idle is rough now yet it is still quite perky considering.

The PO300 code has a 1000 possible causes. :(

A code P0300 may mean that one or more of the following has happened:

Faulty spark plugs or wires
Faulty coil (pack)
Faulty oxygen sensor(s)
Faulty fuel injector(s)
Burned exhaust valve
Faulty catalytic converter(s)
Stuck/blocked EGR valve / passages
Faulty camshaft position sensor
Defective computer

Well my project truck is going to be that for sure but it is still worth $400 at the scrap yard. :)

One plus has been to appreciate the 2002 Blazer with only 192K miles when we drove it tonight knowing it may not be half way worn out yet.

If I can get the 1998 5 speed running well I will drive it a lot and practice on the project truck so when the 2002 needs deep service I will have been there and down that. Plus with two trucks with a lot if interchangable parts it will make swapping parts to trouble shoot easier. If a part off of the 2002 fixes the 1998 I will just put the new part on the 2002.

Short of being a burnt valve or maybe the computer which may not exchange with the 2002 most of the other possible causes listed above are normally replaced items anyway.

Since the is no knocking, decrease in oil PSI, mixing of fluids and still good power even with the PO300 miss I hope I just pushed the miss that was there from time to time into a full time problem that is addressable without a lot of cash.

Before the PO300 occurred an oil change was about the one real need it had as far as I can tell so I am hopeful at this point. If it does not work out I may keep it for spare parts for a while then sell for scrap. Buy-in price less scrap value is just $700. I have had more expense projects as in the MH.

Oh I was going to mention have been running a heavy Sea Foam mix on leaving the seller's place and think that may have loosen some junk in the fuel system perhaps.

There is strong spark from the distributor on all six cylinders so that leaves the wires and plugs to check out. It will start and run with all the plug wires disconnected at the same time on either left/right bank. The only wires that will decrease/increase idle speed (yes it will idle but with a lope) is the middle wire on each bank at the distributor connection?
 
   / Life a Chevy 4.3 V-6 Can Run? #8  
Your problem could be as simple as an oxygen sensor. You may want to change that out first, not as lot of $$
 
   / Life a Chevy 4.3 V-6 Can Run? #9  
They are good motors. A cousin of mine had a 1989 S-10 4WD he put 400k on without any serious motor or tranny repairs. Several water pumps, alternators, and other assorted items along with at least a half dozen fan clutches.
 
   / Life a Chevy 4.3 V-6 Can Run? #10  
Those 4.3l V6's were great engines. It was the same layout (bore x stroke) as the all mighty 350 small block and just about every part from bearings to pistons and valvetrain parts are completely interchangeable. So basically it was the V8 350 with two cylinders chopped off.

I have a feeling you wont see any more 300k+ miles engines nowadays.

I disagree. I worked in a engine plant for GM, and the engines just keep getting better. Better matierals, better metallurgy, tighter tolerances. Biggest problem now is the rest of the vehicle rusting out out well before the engine is done.
 
 
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