Premature Walbro Failure

[JDSfastGN]

Mike if you need another specimen I have a couple of recent failures I can send in to ya. On the other board you mentioned you had posted some info from testing a the Walbro pump that comes in the Ford GT but I haven't been able to find it. I tried to make one work but it didn't work out so well so I was just wanting to see your results. Thanks Mike

 

[Mike Licht]

send those pumps to me if you don't mind. Here are the charts.

 

[Louie L.]

Can you explain what these failures are? Or what symptoms they are showing? Are they just dying and not pumping? Are they acting up when getting hot ? I believe Im having issues with one.

BTW I was suspicious of this specific one as it said Walbro 340 on the body. It was my understanding that the do not have this marking on the body any more. This pump is only about 9 months old.

 

[Mike Licht]

To be honest we still do not see many failures relitive to the amount of pumps we sell, but we do see more than we did in the past. Enough to raise an eyebrow and look for a problem. 340 pumps are still made, so you are good there, the pump that is not made is the 340M which was simply a 340 put in a lathe and made smaller at the inlet (M stood for machined) this allowed it to fit the GM hangar. The pump that replaced the 340M is the F2000169. The failure I see most commonly is that the pump will not make pressure under load, when the car goes up on boost the pressure drops instead of going up with boost causing a lean condition. If other have different problems please post them.
Mike

 

[Junior Samples]

The failure I see most commonly is that the pump will not make pressure under load, when the car goes up on boost the pressure drops instead of going up with boost causing a lean condition.Mike

Thats whats going on with mine right now. Ive went through all kinds of troublshooting, hoping it was the guage, the FPR, vac leaks, lines, filter so forth and so on.
I forget when I puchased it from FT but I installed it this past May, and prolly 2k on it since install.

Sorry to add another one to the list Mike

 

[JDSfastGN]

Mike both of mine have been eratic pressure that slowly drops to 0 and dies. The first pump actually seemed ok after I let it cool for a while. I got it to a friends house and what was strange is that everytime I took the vacuum line off the regulator the pressure would drop and the pump would die. Eventually it completely failed. My last pump that was only a month old died while exiting a freeway exit ramp. After pulling over and priming it would only make about 20 psi and then drop. Neither pump had any debris or material in the inlet screen. I do not know if either gave any warnings of not rising with boost etc... as I don't always have my fuel pressure gauge visible. I'll send it in to you early next week, I would be curious as to what caused the failures as I'm leary of just throwing another one in the car and expecting it to be reliable for the long road trips i subject it to haha.

 

[Bens87tr]

I think I'll stick with my trusty 307 for now. Too many horror stories right now for my taste. No other high output pumps fit?

 

[GNVYUS 1]

Good to see Mike on top of this and getting a meeting is beyond what any of us could have pulled off.

So, would it make a bigger impression to send in every pump that's failed so he's not looking just one?

If he's staring at 15 dead pumps all within a few months from just the GN group that's a pretty powerful impression to not brush off IMO.

 

[84BuickGNYorkPA]

3 pumps in 3 years, extra ground added on pump #2 Thanks for checking this out Mike, my last one I had a fuel gage to see it go up to 48 and that was it. The car ran fine untill I pushed the car into boost.
I would like to say that you got a new pump out to me in 3 days, which was much appreciated.

Chuck

 

[t-topflyer]

I've got 2 possibly 3 that failed on me. All at different times ranging from 2 weeks to 2 years. 1 quit at a stoplight, but did have enough pumping capacity left, although intermittent to get me back home before it quit. 1 quit in a parking lot after I went in get groceries. Did get it cranked there, but it only got me a 100 yards or so down the road before it would not crank back at all (wrecker bill). Last one quit in the driveway of a friends house. Got to use one of his cars to go home and get my trailer, but when I came back it cranked so we drove it to my house. Went out to crank it the next day and nothing. That one lasted the shortest at about 2 weeks.

 

[Louie L.]

Mike both of mine have been eratic pressure that slowly drops to 0 and dies. The first pump actually seemed ok after I let it cool for a while. I got it to a friends house and what was strange is that everytime I took the vacuum line off the regulator the pressure would drop and the pump would die. Eventually it completely failed. My last pump that was only a month old died while exiting a freeway exit ramp. After pulling over and priming it would only make about 20 psi and then drop. Neither pump had any debris or material in the inlet screen. I do not know if either gave any warnings of not rising with boost etc... as I don't always have my fuel pressure gauge visible. I'll send it in to you early next week, I would be curious as to what caused the failures as I'm leary of just throwing another one in the car and expecting it to be reliable for the long road trips i subject it to haha.

This is very similar to what happens in my car. One its hot the FP starts to drop. At some point it will not pump at all. Let it cool off and it runs just fine.

What sucks is that Ive had many 307s in the past never ever with a failure. Wish I had one right now.

 

[A2000RICH]

I do not know of any Turbo Buick vendor selling knock off pumps. I can say for sure that Racetronix and us both use genuine Walbro product. Main cause of pump failures is: sucking air, dirt, alky and low voltage. Most od the pumps that come back so one or more signs of one of these problems when I have Walbro check them.

mike---i certainly understand the first three problems but "low voltage"---how's that gonna cause a dc motor to fail ?------it can of course give symptoms that would cause low pressure/volume but not actual damage to the pump motor-----unlike synchronous ac motors where current increases below lock due to low voltage, a brush DC motor decreases current draw with lower voltage------lower voltage would actually reduce the work done by the motor and allow it to run cooler and last longer--------as soon as the voltage drop external to the pump is diagnosed and fixed the pump should work fine...........RC

 

[Boost231]

wow after reading this im not sure what to do. i bought one of the first 340's about 8 years ago i would say from quad air. it seems fine but i figured it was getting old and maybe i should replace it. is there any way to tell if i should replace it or not. seems fine but its getting some age on it. and after this post i might be better off runnning it.

 

[gusszgs]

Looks like I'll be joining the growing line of people with bad Walbro 340's.
Pretty sure mine's on the way out as I'm only seeing 30-31lbs of pressure now max. This pump was installed with hotwire kit on Tues.....she's only 4 days old. Symptoms of mine were that I was getting NR on full boost and it was getting progressively worse. FP now is around 31lbs line on or off with accufab reg.
Thanks Mike (FT) for looking into the matter. Hopefully we can get some sort of resolution on this issue.
Whats even more frustrating is not knowing where to go from here. I'm reluctant to order another 340 for obvious reasons. Just not many options.

 

[Chuck Leeper]

My DC motor experience comes from 20+ yrs in the lift truck industry. We constantly had problems w/ battery maintence/charging issues, affecting the life of the DC motors. [Hyd pumps and drive motors.]
Our engineering dept gave us a good explanation of what goes on...
Load requires a certain amt of HP to get the job done. [Expressed in watts].
Volts x amps = watts.
Working an example: 36V x 100A =3600 watts to get the work done. Given that the load stays the same, and the volts available drop, due to batt charge level, bad wiring, etc, the equation now looks like this:
Say 30V are available. 3600/30 = 120A. This motor is now drawing 120A, which equals more heat.
In many cases, we saw brush holders, brushes, contactor tips, wire ends, com bars, melted, if the situation got bad enuf.
I see no reason that this scenario would not apply to a DC fuel pump motor??? [Btw, I ran this very scenario past my bud, an EE, w/ many yrs of experience. He agreed]
Since our pump output is directly related to VDC input, [the very reason we use "hotwire kits, and good grounding],
a well established supply of volts, and a corresponding good ground system, would lead me to believe many failures are going to be found elsewhere.. Pump components, level of heat tolerence, tank/sump/return design

 

[Chuck Leeper]

Ok..

Chuck(and all) Walbro just contacted me about your email, I have a pump here that failed on a Buick we are going to meet and he is going to take it apart and try to see what happened. Stay tuned
Mike

I'll watch for updates....
Have you looked at the LS1Tech thread????

 

[Mike Licht]

Low voltage causes excessive heat and premature failure. I spoke to the application engineer yesterday and my thought was that since we have been using hot wire kits and ground upgrades right along with a very smaill percent of failures that something else has changed. He agreed. Although the failure rate is still very low in relation to total pumps sold there is an increase in failures that needs to be checked out. Hpefully we will get me car there next week.
Mike

 

[2 QK 4 U]

I'm a victim too. My Walbro (340) "269" pump only lasted 1 year.

It was not delivering consistant flow. The fuel psi gauge was bouncing all over the place, would not rise above 55psi even at WOT...

I was lucky to get a hold of a good Walbro pump that was several years old. Problems gone, works great.

The chinese are ruining everything...and our govt is letting it happen.

Holley should be able to do something about them knocking off their products.

I guess I might be right about my "chinese" comment after all. You never know where it's made with all the names associated with one part. It's very confusing.

I was lucky to get an older walbro 340 and it's still working great. Also have an old Double Pumper setup with 307's on the other GN that works great.

 

[Just a Six??]

You guys with dead pumps should send them to Mike so they can be inspected. I mean they are of no use to you now. Maybe help the greater cause for everyone down the line.

 

[Chuck Leeper]

I'm sure they will want to know details, such as:
Purchase date.
Operating voltage.
Operating pressure, and max pressure.
In retrospect, it could be that we are operating the pumps at a higher idle psi, as well as a higher max psi, than the OEM specs called for.
Gasolene chemistry has changed. [It would be interesting to see the MTBF, with a fuel lube, such as Klotz, vs no additive].

I guess I'm really "outta my box"....Back under the injector bench.