4.3 L engine - high mileage

Eight years ago I purchased my used 1995 Chev Blazer, it has 75,000 km and just off a two year lease. It now has 526,000 km and has given no trouble what so ever. I change the oil and filter every 5,000 km, this gives the life to any engine and I mean it. It runs smooth, if you watch what type of gas you put in it. At 500,000 km I treated it to a new set of spark plugs and wires. The old plugs were worn a bit but no sign of engine problems were indicated on the plugs. I have read that some think the 4.3 L engine is the worst thing ever invented. I guess I have the "one" that will give good performance for a long time to come yet, I hope. Perhaps those who do not have very good luck with their vehicles are the ones who abuse them.

Reply to
wheat
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There is nothing wrong with a 4.3 as it is based on the long proven

350 and has not design defects to impair long life. I think most how complain about them over work them with big tires with stock gears or big loads with improper gearing. As you discovered that 4.3 can be a workhorse with cared for properly. I would suggest that you might stop using 5w30 in it except in very cold weather (use 10w30) and in hot weather try 15w40 as it will reduce oil consumption that may be effecting plugs.
Reply to
SnoMan

That's news to me, I've always heard of the 4.3L referred to as a very tough engine. It's only really major problem is that it's missing two cylinders. You have to be trying pretty damn hard to kill 'em.

Reply to
SBlackfoot

He must have been referring to the 2.8 from the 80's.

Reply to
Adam Frazier

On my previous motor, a valve stuck (130K), punching a hole in a piston (granted a smallish one) and I was able to limp 70 miles home with little problem. Sure it ran rough, but it got me there. I went the easy route and put a new (crate from GM) 4.3, but I thought long and hard of doing the 350 conversion.

Big Chris

SBlackfoot wrote:

Reply to
Big Chris

Hah! Good to hear!!!

My 2002 4.3L has 40,000 miles. I use synthetic Mobil1 and have since mile

6000.

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Reply to
True Blue

This wouldn't be a full size blazer would it? Anyway, the owner's manual for my 95 S-10 4.3 says its ok to use 10-30, but not 10-40, or 20-50, or any other grade oil. Except for straight 30w at temps above 40F.

Reply to
D.Murphy

Probably not. To clarify, all the *older* mid '80s 5.7s and 4.3s had a real bad problem with the valve guides getting larger as the valve stem moved over time and the valve seals getting brittle and cracking thereby letting oil drip into the cylinders that were left open after the engine was shut off. They were real oil burners. Largely by '89, GM fixed that problem but for some reason only the 4.3 is really remembered for that problem.

ZZZ

Reply to
zzz

My '90 305 still has that issue, and I've recently been told my '91 4.3L puffs a little on startup too (must be new, it never had before.). Seeing as how it only puffs for a few seconds at startup while the seals swell up and that it's reasonably easy to repair on an sbc I really don't see it as a reason to condemn the engine as a whole.

Reply to
SBlackfoot

My 91 started burning a bit of oil on start-up around 130K but replaced it with a rebuilt around 155K....My only complaint: lack of power on hills, but it goes great on the flats (about 18-20 mpg on the piss poor crap Calif calls "gas")

Oh yeah, the piston slappin' went away too

Reply to
ken

Reply to
Jeffery P.

Stuck valve are cause by two things, a really gummed up valve guide form poor maintainance practices or lousy oil or from over reving the engine and the piston hits a valve and bends it so it cannot retract and damage results. A 4.3 is no more (or less) prone to a valve sticking than a 350 is.

Reply to
SnoMan

Yeah, I realize what causes a stuck valve. In my case it was the old bugger who owned the truck before me and was a bit abusive to it. I wasn't considering the 350 swap to avoid the valve problem. I was considering it because it wasn't a whole lot more work or money for a lot more power.

Big Chris

SnoMan wrote:

Reply to
Big Chris
1 mile equals how many km?

Reply to
KMU

Reply to
Mike Levy

Oh, I forgot to add, my S-10 has over 300k miles on it, and it still has orginal engine and trans, and it will still shit and get.

Reply to
KMU

If this is a CPI equipped engine it could be a bad injector unit. They sometimes fail and dump raw gas into the intake, causing rich mixture that the computer cannot control.

Reply to
Steve W.

My last Silverado had the 4.3 in it and it would chirp the tires easily... it had nearly 300,000 on it when it was totaled by a guy coming off the highway (yah, it was as bad is it sounds). The only problems that engine had was the blow-by was so bad that it actually shot oil mist into the PCV and then the mist got sucked into the carb. I had to extend the PCV valve out a few inches from the valvecover to correct it. The other problem was really not the engine, but rather the Q-Jet carb. The damn air bleeds would adjust themselves out over time. (The Silverado was an '86)

ZZZ

Reply to
zzz

a good valvecover cleaning now and again will help that problem with the blowby. MMO or Lucas seemed to help as well . A good synth oil will probably prevent the gumup of the covers to begin with.

Now my 4.3 story. I've had my Blazer since 99. . I bought it with 170K miles on it and it now has over 250K miles

Reply to
burntkat

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