Balance Shaft myth debunked!!

[boominXplorer]

If they are white they are the last version, mid 2007

 

[2000StreetRod]

Does any body knows how many miles before the timing cassettes can became an issue?
My vehicle is an 2006 and I am replacing it with a 2008 engine, I know that ford corrected or redesigned the cassettes but do not know in which year that iwas corrected.
I am hoping someone has an idea of what year the correction was made and hopefully I won't have to make any changes and just install it as it is.

There were no improvements to the cassettes or the tensioners after the 2002 models. In my opinion the remaining weakest component is the right (rear) cassette guide.

The chain slack side of the guide is reinforced with metal but the traction side is still entirely plastic. It fails the same way the old style failed.

My original guide failed at 150K miles.

 

[CDW6212R]

Thank you for the info,
I got another engine with 60000 miles on it.
I am thinking on replacing the upper and lower oil pan gaskets as well as the timing cassettes just because it will be already out and hopefully won't have to mess with it for a while.
Does any body knows how many miles before the timing cassettes can became an issue?
My vehicle is an 2006 and I am replacing it with a 2008 engine, I know that ford corrected or redesigned the cassettes but do not know in which year that iwas corrected.
I am hoping someone has an idea of what year the correction was made and hopefully I won't have to make any changes and just install it as it is.

The timing cassettes were improved, not corrected, in the early 2000's. They all have shorter lifespans than typical internal parts, which often are 150k miles. Long ago the early SOHC models were turning up with issues way under 100k miles, and now some of those same engines are still going unaltered with close to 200k miles.

So there isn't a known age limit on any of these, it's our opinions, and Ford's opinions we are discussing. Ford only put out a service bulletin on the first five years and 75k vehicles, so we are way past that. Now it's about some revised parts, and the same problem with the tensioners which have not been updated.

I believe the external tensioners are the biggest worry, the springs inside of those do wear out, get weaker, and I think about 75k is about all one should hope for from those. Gladly those are the easiest things to change.

The plastic guides of the timing cassettes will always be a weak link, they get fragile over time, weaker, and they wear down. Those I'd expect to last 100-200k miles, depending on how well the engine was taken care of. Cheap dino oil and long intervals between oil changes is very bad for parts, especially plastic parts with metal chains riding on them constantly. You want full and slick oil on those parts at all times, and at each start up there is none.

 

[waren]

i am on a SOHC information crash course and just want to add my thanks to the long list of people you guys have helped. At this point I’m noticing some start up noise when cold not sure if it’s accessory drive or timing, I suspect timing issues just starting with 100k miles on engine.

In one of 2000Streetrod’s other detailed threads on SOHC V6 timing he mentioned he is no longer recommending replacement of the external tensioners due to weak springs even in the OEM parts ... I can’t recall exactly the date of that post, but I think it was prior to CDW6212R’s 2019 post above.

Just wondering if the OE external tensioners springs are better again (maybe ford changed suppliers).

Also in one of the posts I read it was more cost effective to buy the service kit

Ford Recall / Service Kit #00M12
contains improved Tensioner, Intake Manifold Gaskets and mounting material
Part No.: YL2Z-9E473-AA

Does this service kit also contain the parts needed to remove and block off the balance shaft?

 

[CDW6212R]

The external tensioners have two weaknesses that affect their lifespan. The actual spring inside will last a variable amount of time, that's an unknown.

There is a small check valve inside those two tensioners, which trap oil inside to help the spring push outward. That valve has a rubber outer seal on it, and over time it becomes hard and brittle, like any common transmission accumulator etc. That seal can and will eventually not stop the oil from leaking back out, which reduces the effectiveness of the tensioner.

Plus add to that the possibility of tiny debris getting inside the tensioners, and blocking the oil passage in some amount. Thus, the tensioners are not likely to last extended periods of time or mileage. The quality of oil and filter used is very important, and some engines will get better service from their tensioners. Some will need help sooner than others.

 

[imp]

Unable to read through the entire thread, here's one thing troubling me? EVERY maker of vehicles offers a V-6 engine. How do the OTHERS solve this vibration mystery? I know V-6 of 60-degree cylinder angle is inherently ill-balanced. Do others use a balance shaft? Which ones? And do those without run "rougher" than those with the damned thing?

 

[waren]

The Physics of Engine Cylinder Bank Angles

Why the angle between banks is critical to a smooth-running engine.

www.caranddriver.com

I am no expert ... this article probably covers it better than I ever could. essentially the mass of the moving parts of the engine needs to be balanced in addition to the forces produced by the combustion cycle. A balance shaft in largish displacement unbalanced designs is a common solution.

years ago I was obsessed with getting a flat plane crank (and matching custom ground cam) for a small block ford project. Too bad I couldn’t afford the production version ford finally made for the mustang.

Maybe what makes the 4l SOHC V6 timing layout particularly convoluted is the fact that SOHC heads were essentially a retrofit. I had no idea the passenger head was driven off the back of the engine. So I guess the heads are identical D/P? Maybe if the system lasted the life of the engine that would be a win .... but honestly I’d rather have a timing belt. At least I wouldn’t have to pull the engine to change it.

Ford Cologne V6 engine - Wikipedia

en.wikipedia.org

 

[1991 sploder]

about the balance shaft... Their meant to smooth out the motor at idle usually...even some 2 cylender Harleys and alot of 4 cylenders have them....i guess it's because consumers want a smooth idle... At a high rpm is when the balance shafts are useless...if anything ur better off without them at higher rpm.. I'm considering a motorcraft tattoo hahahah

 

[CDW6212R]

Unable to read through the entire thread, here's one thing troubling me? EVERY maker of vehicles offers a V-6 engine. How do the OTHERS solve this vibration mystery? I know V-6 of 60-degree cylinder angle is inherently ill-balanced. Do others use a balance shaft? Which ones? And do those without run "rougher" than those with the damned thing?

I thought I had read these 4.0's were a 70 degree angle. But it's no big deal, the balance shaft has obviously been shown to be unnecessary by many members before.

I went through the trouble of re-timing my balance shaft after I found it was off during my work on the timing chains. Removing the balance shaft was not really hard, but I'd rather not do it, and its tiny tensioner broke after I was done. That tensioner for that tiny chain is very fragile, being able to do without that alone is worth doing away with the balance shaft.

 

[waren]

Hey, Dillard000 thanks for clarifying. when I read the TSB I noticed that there were two versions of the service kit. I hoped that the non balance shaft version would contain parts needed to correctly delete but totally makes sense that it does not.

I agree with others here that the balance shaft was likely added for the low range use case. I also would like to delete for the benefit of simplification. StreetRod2000 recommended leaving the shaft in place to prevent unrestricted oil flow. I read multiple references to users plugging the oil passages. Does anyone have details on the plugs required?

TSB 04-15-4 RATTLE NOISE FROM PRIMARY CHAIN DRIVE AREA 2000-3000 RPM - 4.0L SOHC ENGINE

FORD: 1999-2002 Explorer, Mountaineer
2001-2002 Explorer Sport Trac, Explorer Sport, Ranger


This article supersedes TSB 02-08-01 to update part numbers and add a labor operation for vehicles with auxiliary air conditioning.

ISSUE:
Some vehicles equipped with the 4.0 SOHC (single over-head cam) engine may exhibit a primary timing chain rattle noise. The noise is heard during hot and cold engine operation (but mainly heard on cold engines) under acceleration, typically at 2400-2500 RPM. To verify concern, accelerate in 2nd gear between 2000 and 3000 RPM and listen for rattle noise that sounds similar to spark knock. This may be caused by the primary timing chain tensioner system.

ACTION:
Replace the Primary Timing Chain Tensioner, Chain Guide, Jackshaft and Crankshaft Sprockets with a Primary Timing Chain Tensioner Kit. The Kit includes an improved Primary Chain Tensioner, as well as updated Primary Chain Guide, Primary Jackshaft, and Crankshaft Sprockets. Required fasteners, Primary Timing Chain, and Front Cover Gaskets are also included. Refer to the following Service Procedure for details.

SERVICE PROCEDURE

Verify the condition. Obtain the correct Primary Timing Chain Tensioner Kit and follow the instruction sheet supplied with the Kit.

Use Kit 2U3Z-6D256-CA (balance shaft engines) for:

1999-2001 4X4 Explorer/Mountaineer
2001-2002 4X4 Sport/Sport Trac
ALL 2002 Explorer/Mountaineer, except engine codes 2G-960-AA and 2G-964-AA.

Use Kit P/N 2U3Z-6D256-DA (non balance shaft engines) for:

1999-2001 4X2 Explorer/Mountaineer
2001-2002 4X2 Sport/Sport Trac
2002 MY Explorer/Mountaineer with engine codes 2G-960-AA and 2G-964-AA
ALL 2001-2002 Ranger

 

[imp]

I thought I had read these 4.0's were a 70 degree angle. But it's no big deal, the balance shaft has obviously been shown to be unnecessary by many members before.

I went through the trouble of re-timing my balance shaft after I found it was off during my work on the timing chains. Removing the balance shaft was not really hard, but I'd rather not do it, and its tiny tensioner broke after I was done. That tensioner for that tiny chain is very fragile, being able to do without that alone is worth doing away with the balance shaft.

"The original Ford Cologne V6 is a series of 60° cast iron block V6 engines produced continuously by the Ford Motor Company in Cologne, Germany, since 1965. Along with the British Ford Essex V6 engine and the U.S. Buick V6 and GMC Truck V6, these were among the first mass-produced V6 engines in the world."

 

[CDW6212R]

"The original Ford Cologne V6 is a series of 60° cast iron block V6 engines produced continuously by the Ford Motor Company in Cologne, Germany, since 1965. Along with the British Ford Essex V6 engine and the U.S. Buick V6 and GMC Truck V6, these were among the first mass-produced V6 engines in the world."

Thanks, that sounds right and I don't know where the 70* figure came from for me. I really like the 4.0 platform except for the poorly executed OHC design. The 2.9 DOHC version was a great engine, and if they had made the 4.0 with that chain drive, I bet it could have rivaled the hp/ci of the modern foreign engines. But I gather the piston and rod sizes are unique and thus very expensive in any custom versions. So the engine has little aftermarket support, and the stock timing system needs extra care.

 

[Devan]

point taken fellas, I talked to a guy who has had (2) 2wd engines go south on him in a 4wd; I am now eating my words. he said the first one had no vibration but had the timing chain go. The second engine started out with a little vibration and then two months later it felt like a washing machine on the spin cycle. Do any of you guys have any clue as to why this problem would get progressively worse??? I haven't noticed anything so far but have only driven it a small distance. The engine I have in it has only 45k on it and not really wanting to risk messing up the engine. Anyone think this guy just had used engines prone to failure regardless of the fact that they were in a 4wd?

wellll, see what happens when you put an engine without a balance shaft ina truck thats suppose to have a balance shaft? It unbalances itself into pieces like a way off center washing machine load roffl. jk

 

[BUXTER]

We were successfully deleting Balance Shafts 30 years ago in the Mitsu World... BTW there's a GOOD REASON Kamikaze's flew Mitsubishi's ~! - Most of the Kamikaze Pilots were previous Mitsu MECHANICS... being a Kamikaze was WAY more fun than working on Mitsu's.