U/D Pullies = Oil Pump Failure?

[Rider90]

This is a very often discussed topic at the Mach1 boards, of whom share the same 4.6L DOHC engine that we have. I guess I have two questions that I hope the powers of higher knowledge can answer for me...

1) Do the Mach1's have different pullies than us? I'd say about every 8 of 10 people that do the U/D Pullies (Mach1) report zero gain, or say they have lost power, and describe U/D pullies as a waste of money.

2) Is an oil pump failure possible from U/D pullies? There have been a handful of Mach1 owners that have had the oil pump fail after doing this mod. How about any problems with the A/C?

It seems that over here at this board we praise the underdrive pullies for what they do for our land yachts, so it would make sense if the pullies between our Marauders and their Mach1s are different. I read somewhere on their board that they (we?) already have Ford's version of underdrive pullies.

"The harmonics of the underdrive pulles are causing the cast oil pump to fail." - Mach1 Board

Related Thread - http://www.mach1registry.org/forums/...ad.php?t=31092

[FordNut]

Lots of info can be found here on that subject with a search, but in a nutshell here's a recap...

Steeda pulleys have a one-piece crank pulley that replaces the OEM pulley/damper. Nobody here that has used that type has had a failure related to the pulleys. Some other brands use a piggy-back arrangement on the OEM damper. The instructions for the pulleys are not always included or clear or even followed, so some folks have improperly installed this type of pulley whick resulted in oil pump failure.

The alternator pulley is usually not changed on our cars for a couple of reasons. One being the fact that the '03s had a special one-way clutch on the alternator so it was inconvenient to change it, another being that the MM has so many electrical options that it's not wise to reduce the alternator output any further than the crank pulley reduces it.

Many of us have done dyno tests before and after mods to verify gains. Most of us have experienced about 10 hp from the underdrive pulleys.

[Rider90]

FordNut, is there any other way for the oil pump to fail after an U/D pulley install, or is it just that they were not installed right?

There are a lot of posts out there shunning the U/D pullies and only a few praising them. Why would so many have negative effects....

[cyclone03]

Some installers use an impach wrench to remove and install the new damper.
That sends shock waves into the oil pump gear mounted on the crankshaft cracking it.


I got involved in a discussion with a guy on a message board who was going on his 4th(!) new lower end.He blamed pretty much everybody who ever looked at his car for this failure.He was running a very modded Mustang with a supercharger.On the street all was good,but at the track AFTER he lifted at the end of a run the oil pressure went to zero (everytime).

Back and forth we went,I asked him to list all his mods and when he said Underdrive pulley's I asked about the damper,he said NONE BECAUSE THATS THE WAY EVERYBODY RUNS THEM,I said does everybody help you rebuild your moter?

He hasn't broke it yet....

[Rider90]

So use hand-tools and nothing air powered?

[SergntMac]

Missing or incorrect dampner is the major cause behind failed oil pump. If the crank snout isn't properly counter-balanced, the oil pump gears will suffer.

Some engines are internally balanced, some are not, therefore, UD manufacturers do not always include a dampner, or, advice about them. If the Mach I owners are trashing their oil pumps, most likely it's because one owner used an incorrect set of pulleys and everyone followed his lead rather than making their own decision. This is an underlying problem with user boards like our MM.Net here. One guy does something, everyone jumps off the same cliff.

Best to check with a pro engine builder, and see which set of UD pulleys are correct for your applcation. Our shared 4.6L DOHC is not internally balanced, and a dampner is absolutely necessary. That said, you have a few styles and weights to choose from, some of which are NHRA certified for racing use.

If I were to go shopping for UD pulleys today, I'd buy the Steeda set from Reinhart. Many of us here have, with no complaints.

[Smokie]

.....or maybe the Mach 1 guys are installing the crank pulley with the longer bolt that comes with the Steeda kit...

[metroplex]

The mod motors are internally balanced. We do not have balancers. The dampeners are integrated with the crank pulley. The piggeyback pulleys will run into problems with distortion and unbalanced rotation.

I used air tools for my install. I know a lot of people that use air tools for that installation. If the oil pump gears crack from the vibration then those gears shouldn't be used in such an application.

[Blackened300a]

I installed my Pullies with Airtools about 3 months ago and I definitly felt a improvement in acceleration off the line. I also have had No problems with them

[CRUZTAKER]

No troubles here after some 20,000 miles.

Definate numbers and perforfance increase however!

[Rider90]

Which U/D pullies are you guys using and from where? Steeda? DR?

Any other problems?

[SergntMac]

The mod motors are internally balanced. We do not have balancers. The dampeners are integrated with the crank pulley. The piggeyback pulleys will run into problems with distortion and unbalanced rotation.

I used air tools for my install. I know a lot of people that use air tools for that installation. If the oil pump gears crack from the vibration then those gears shouldn't be used in such an application.

I disagree. All 4.6 and 5.4 crankshafts are neutral balance, static balanced outside the block, which is to say that absent a heavy flywheel, or, balancer, the crank does not have a counterweight to match it's natural imbalance under power, or, while suffering the violence of detonation. Detonation isn't just spark knock, it more like two automobiles hitting head on. This is a lot of violence to the crank, even briefly, and the balancer must be up to the task.

Balancers come in several flavors, depending on the crankshaft. Some are fixed weight, others are adjustable and all you to add/remove weight, depending on your final application and tune. The oil pump failures on engines using stock oil pumps can be attributted to a harmonic problem that manifests itself by breaking the oil pump gears when inadequate dampening from a reduced diameter harmonic balancer is employed. Just because a particular UD kit includes a harmonic balancer/damper, doesn't mean it's big enough to act as the counterweight in a particular build. Look at the hiistory of balancer/dampers as our Ford V-8 has changed.

The '96-'98 Mustang GT used a balancer with a .290 inch outer ring depth. The '96-01 Cobra and the '93-98 Mark VIII used a .560 inch outer ring, while the '99-'03 GT used an .800 inch outer ring. Finally, our Marauder and late model Mach Is with auto trannies use the thickest outer ring depth yet, 1.15 inch and weighing in at 9.90 pounds. Robust, eh? If the cast cranks were truely internally balanced, this ring and it's weight wouldn't be necessary.

Removing the balancer, or, using an aftermarked balancer that isn't adequate for the task will result in failure, when the oil pump gears are reduced to sand by an out of balance crankshaft. I used the Steeda kit on my N/A Marauder with no complications, and I observed 10 RWHP and 7 RWTQ on back to back dynos. If a supplier doesn't list the Marauder specifically, use the Mach 1 kit, or, the '99-'03 Mustang GT kit. Yes, it's a 2 valve engine, but the bottom end is the same.

I don't have UD pulleys on my supercharged Marauder, but I did replace the OEM damper to match the upgraded Ford Racing forged crank, which was re-balanced in the build. The damper is Ford Racing M-6316-D461. BTW, I am very comfortable using the OEM oil pump and gears, and I am just shy of 500 RWHP.

I don't see any relationship between using air tools and complications with the oil pump. However, common sense says bolts should be broken loose (and final torque) by hand, or discarded and replaced with fresh bolts, IMHO. Constant pounding from an impact gun isn't good for any bolt.

[Rider90]

Mac, in a post I recall you saying you held on to your U/D pullies and now you say you have none installed....is that saying you might have a set for sale?

[cyclone03]

.....or maybe the Mach 1 guys are installing the crank pulley with the longer bolt that comes with the Steeda kit...

Yea thats bad too....

[cyclone03]

Your confusing balance weight with harmonic dampening.

Balance is like a titer-tooter the weight of the piston rod combo needs to be offset buy the counter weights on the crank shaft,and it is.All the balance function in all Mod motors is handled by the crank.
If the engine was EXTERNALY balanced,like the Ford 289,302,351's we would have an OFFSET weight on the crank damper and flywheel.


The weight ,or mass, of the damper is used to ,well,dampen the harmonic vibrations that the pounding of combustion send into the crankshaft.This vibration,if not controled is what kills the brittle oil pump gears and if somehow was left unchecked can take out rod and main bearings too.


Oh and yes the stock or even any crank damper could be lightened or balanced along with the complete rotating assembly. But our engines should have all balance work done internaly.