3.8 vs 3800

[MarkV]

So, what is the difference? which lasts longer? are the parts transferrable between both? how long do they last?

[JohnD1956]

There are differences, and the parts are not interchangeable. Of the two, the 3800 is the longer lasting motor. Of course, you can most always find a long lasting survivor in the 3.8 too, but I believe the 3800 has lots of long lasting engines.

[NTX5467]

The significant difference in the Buick 231 and Buick 3800 V-6 is that the 3800 has a balance shaft and the Buick 231 does not. Depending upon which year it is, the Buick 231 can be "Even Fire" (later verions, later 1970s) and the prior Buick 231s were "Odd Fire"--look at the spacing on the distributor cap.

The Buick 3800 saw continual development and refinement with almost every year. One year, for example, the fuel injectors were targeted better in the intake manifold (toward the intake valve head). It was these refinements which led to the eventual horsepower rating increases from about 160 to 195-210 (determined by model year and model of vehicle--for the naturally-aspirated versions). Seems like, somewhere in that mix, there was a pretty much significant re-design of the rotating assembly to what the last versions were?

When we went through the V-6 engine plant at the 1988 BCA National Meet in Flint, the Buick 3800 was still pretty recent. There was a chart displayed on the plant floor which showed main bearing life in "Proving Ground Miles" -- the 231 had main bearing life of about 10K Proving Ground Miles and the 3800 had main bearing life of about 80K Proving Ground Miles. Looks like taking some of the harmonics out of the engine with the balance shaft very positively-affected the life-span of the whole rotating assembly and related bearings. Of course, "Proving Ground Miles" are much more severe than "Consumer Road Miles"--typically.

By observation, there generally were NO issues with the guts of the 3800 motor. Things like the harmonic balancer-pulley, the "Interrupter" (located in the camshaft sproket) magnet which could fall out, and some intake gasket issues on the later models are about IT.

On the 231s, there were some issues with the Mass Air Flow sensors sporadically causing issues, as the Magnavox ignition systems usually would (not a Wurlitzer??).

That's about all I can think of, for now . . . it's been a good while since I sold ANY parts for a Buick 3800 V-6! Of course, some people could tear up the proverbial anvil in a sand pile, too.

Enjoy!

NTX5467

[MarkV]

well I am looking at an 87 lesabre with 200,000 and kept up in good condition and the motor rebuilt the guy only wants a grand for it.

[Centurion]

I recently read on another forum about a woman who has crossed the 400,000 mile mark with her '89 LeSabre with the 3800.

[Dons]

On 4/10/2010 at 11:22 PM, NTX5467 said:

The significant difference in the Buick 231 and Buick 3800 V-6 is that the 3800 has a balance shaft and the Buick 231 does not. Depending upon which year it is, the Buick 231 can be "Even Fire" (later verions, later 1970s) and the prior Buick 231s were "Odd Fire"--look at the spacing on the distributor cap.

The Buick 3800 saw continual development and refinement with almost every year. One year, for example, the fuel injectors were targeted better in the intake manifold (toward the intake valve head). It was these refinements which led to the eventual horsepower rating increases from about 160 to 195-210 (determined by model year and model of vehicle--for the naturally-aspirated versions). Seems like, somewhere in that mix, there was a pretty much significant re-design of the rotating assembly to what the last versions were?

When we went through the V-6 engine plant at the 1988 BCA National Meet in Flint, the Buick 3800 was still pretty recent. There was a chart displayed on the plant floor which showed main bearing life in "Proving Ground Miles" -- the 231 had main bearing life of about 10K Proving Ground Miles and the 3800 had main bearing life of about 80K Proving Ground Miles. Looks like taking some of the harmonics out of the engine with the balance shaft very positively-affected the life-span of the whole rotating assembly and related bearings. Of course, "Proving Ground Miles" are much more severe than "Consumer Road Miles"--typically.

By observation, there generally were NO issues with the guts of the 3800 motor. Things like the harmonic balancer-pulley, the "Interrupter" (located in the camshaft sproket) magnet which could fall out, and some intake gasket issues on the later models are about IT.

On the 231s, there were some issues with the Mass Air Flow sensors sporadically causing issues, as the Magnavox ignition systems usually would (not a Wurlitzer??).

That's about all I can think of, for now . . . it's been a good while since I sold ANY parts for a Buick 3800 V-6! Of course, some people could tear up the proverbial anvil in a sand pile, too.

Enjoy!

NTX5467

Having a hard time figuring out the noise on my Buick. Does my 1986 Buick Electra park avenue with the 3.8 have a balance shaft? 

[Dons]

On 4/10/2010 at 11:22 PM, NTX5467 said:

The significant difference in the Buick 231 and Buick 3800 V-6 is that the 3800 has a balance shaft and the Buick 231 does not. Depending upon which year it is, the Buick 231 can be "Even Fire" (later verions, later 1970s) and the prior Buick 231s were "Odd Fire"--look at the spacing on the distributor cap.

The Buick 3800 saw continual development and refinement with almost every year. One year, for example, the fuel injectors were targeted better in the intake manifold (toward the intake valve head). It was these refinements which led to the eventual horsepower rating increases from about 160 to 195-210 (determined by model year and model of vehicle--for the naturally-aspirated versions). Seems like, somewhere in that mix, there was a pretty much significant re-design of the rotating assembly to what the last versions were?

When we went through the V-6 engine plant at the 1988 BCA National Meet in Flint, the Buick 3800 was still pretty recent. There was a chart displayed on the plant floor which showed main bearing life in "Proving Ground Miles" -- the 231 had main bearing life of about 10K Proving Ground Miles and the 3800 had main bearing life of about 80K Proving Ground Miles. Looks like taking some of the harmonics out of the engine with the balance shaft very positively-affected the life-span of the whole rotating assembly and related bearings. Of course, "Proving Ground Miles" are much more severe than "Consumer Road Miles"--typically.

By observation, there generally were NO issues with the guts of the 3800 motor. Things like the harmonic balancer-pulley, the "Interrupter" (located in the camshaft sproket) magnet which could fall out, and some intake gasket issues on the later models are about IT.

On the 231s, there were some issues with the Mass Air Flow sensors sporadically causing issues, as the Magnavox ignition systems usually would (not a Wurlitzer??).

That's about all I can think of, for now . . . it's been a good while since I sold ANY parts for a Buick 3800 V-6! Of course, some people could tear up the proverbial anvil in a sand pile, too.

Enjoy!

NTX5467

Does my 1986 Buick Electra park avenue with he 3.8 have a balance shaft??? I’m having a hard time figuring out an engine noise.  

[NTX5467]

Check the lower crankshaft damper/pulley for a loose balance weight behind the pulley part.  The balance weight is held in place by rubber.  When the rubber delaminates from the metal, the weight has a limited "swing", as the metal is mounted onto the pulley by a bearing so it can move, but when it does swing, it can cause a noise when the engine starts or stops.

 

As to the balance shaft, it is model year specific and all emblems should indicate "3800" rather than 3.8 Liter.

 

NTX5467

[Barney Eaton]

MarkV  if you like the LeSabre and it is rust free......take a chance.    Even if you have engine problems and the rest of the car is good it could be upgraded with a 1988 and later 3800 engine...they made millions of them

Buick, Olds, Pontiac and Chevy used the 3800 engine so there is a good supply of engines and since they are bullet proof,  there is not a big demand for used engines....

[EmTee]

I owned a '90 Bonneville with the 3800.  I replaced the timing chain and gears at 110 Kmi because the chain was getting noisy and I wanted to replace what I thought would be a nylon-toothed cam gear.  To my surprise, I found steel gears and behind the cam gear a balance shaft!  I remember being impressed with the way it was put together.  With the new chain , tensioner and gears I drove it for another 40+ Kmi.  That car was a runner - and I wouldn't hesitate jumping-in and driving it cross country.

[60FlatTop]

Here is my 1986 Park Ave the day it arrived in 2010.

 

It was not running at the time and the problem was very obviously neglect of oil changes. The previous owner said there was a loud noise in the engine when it ran. We couldn't even start it. And the transmission didn't work either. All I saw was poor maintenance, no sign of inherent design issues. I have been driving it 500-600 miles a year for the past 10 years and it is a very acceptable little car. Most of my old car driving is the '60 Electra so there is a significant difference.

 

I bought a new short block for it, had the heads done, and rebuilt or replaced almost everything mechanical on the car. I am into it for about $9,000 total but tht was in 2012, haven't spent much since. Another $2500- 3,000 into paint and cosmetics will finish the ToDo list.

 

My wife keeps hearing that when the paint touch up gets done I will put it up for sale. I think she is beginning to catch on to the delay. Maybe some new carpets for '23 and another year'd delay.

 

I overdo most work. Like the Imron subframe.

 

And here is a treat. I found a set of Genuine GM NOS wheels... straight from Japan.

 

[Centurion]

On 11/16/2022 at 3:07 PM, Dons said:

Does my 1986 Buick Electra park avenue with he 3.8 have a balance shaft??? I’m having a hard time figuring out an engine noise.  

The 3800 was introduced for the 1988 model year.  Your 1986 model would not be a 3800 and lacks a balance shaft.

[MRJBUICK]

The 3.8 or 231 hit the scene in 75 as an odd fire version of the 350ci v8 with 2 cylinders chopped off

the even fire 3.8 came in 79

the 3.8 went through many changes til 88 which was a split year change to the 3800

the 3800 had 3 series with the last i think being an on center motor

so you have to be careful changing parts from a generation to a different generation

all the later 3.8 and 3800 motors are good motors just look for what you would normally look for when buying one

Good Luck

Marty

[60FlatTop]

We avoided a potential disaster after installing my short block by using a gauge to test the oil pressure before starting. My car uses a VIN code 3 engine. I used a Felpro gasket kit claimed to be the proper application. We could not establish pre-start oil pressure.

It turned out that our new timing chain cover gasket blocked the oil port. Luckily, we checked with a Buick mechanic who handed us one and said "You gotta use this one". It turns out that the VIN 3 engines switched to a crankshaft driven oil pump when they went distributorless and changed the timing chain cover porting.  Whodda thunk. My nephew caught it because he is a\bout as unforgiving with assumptions as I.

 

We could have lost the new engine without our checklists.

 

There are some peculiarities in cars that experience will provide specific answers to and the 3.8 variety is one as they become older. Hidden in memory or not the basic checks brought the issue to light. It may have taken longer, much longer, to find the blocked passage. But there was no way it was going to be started with oil pressure in question.

 

Don Rumsfeld said it best:

 

"because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know."

 

"Atta boy, Donny" (Also my nephew's name).

Edited November 19, 2022 by 60FlatTop (see edit history)

[dship]

Over the years, after Buick bought back the 3.8/3800 V6 rights from Jeep (I believe?), the engine evolved little by little throughout its production years.

[MRJBUICK]

i had an 87 Lesabre coupe that had the 3.8. It turns out the cam gear had the plastic,

although mine had non of it left when i dropped the pan and found most of it in the pan. the car had trouble starting and finally wouldnt start, but when running ran ok, it turns out the computer was compensating for the loose timing chain, kinda scary actually.

once the motors went to crank oil pump it solved all oiling issues and durability went up.

i always fount the 3.8 front drives a little more aggressive in running ( i call it snottier lol) where the 3800 is more smooth and refined, i would take any of them in a heartbeat.

i had a 05 Lesabre with a series 2 3800 those easily will go over 200k if the rest of the car lasts 

Marty

[dship]

I've had seven 3800's over the years; five of them naturally aspirated and two super charged.  Never had a problem with any of them.  I just kept them well maintained.  These iron babies just don't quit. 

[NTX5467]

Many might perceive that with the same engine family and displacement, "they are all the same", which is certainly NOT true on the Buick V-6s of 3800cc displacement.

 

In the later 1980s, pre-GN, whenever the horsepower would be increased, there was a reason.  Like one model year, it was due to a re-targeting of the fuel injectors in the ports.  An evolutionary change for emissions, I suspect, which also resulted in a power increase.  For another model year, they re-designed the cyl block, which means things which bolt to it CAN be different, too.  Then, they re-designed the front of the engine to use a large aluminum casting to house the water pump and heater water conduits, which is when they sold that casting with the belt idler on it, as ONE part number.  If you needed just an idler, from GM you got that whole deal.

 

That particular re-design also resulted in the heater hoses attaching do that casting, held on by bolts.  The first-design hoses only had ONE o-ring to seal them there, but due to vibrating heater cores (due to "magnetic resonance" as the Buick TSB called it!), the 2nd-design hoses had TWO o-rings on them for sealing.

 

End result is to ALWAYS buy parts by the engine VIN Code and model year.

 

Kind of interesting that when GM standardized all of their then-new line of full-size FWD cars to use the Buick V-6, as high-tech at it was at the time with EFI, distributorless ignition, etc., that JDPowers ratings for those cars went up a good bit.  Even without balance shafts, which came later.  Usually, as long as they had anything close to decent oil and filter changes, they would last a very long time, by observation.

 

Just some recollections,

NTX5467

[60FlatTop]

That sounds familiar. Like Fizzbin.

 

 

And never top off the coolant after midnight.

[NTX5467]

Just curious . . . "Never top off the coolant after midnight" . . . in which time zone or spatial location?