Walbro Pump - Cause - Alternator Overcharging!!!!

**TurboRA28** · 04-10-2006, 01:36 PM

Interesting.. yes mine does change pitch often but being external it has no strainer and is fed from a 4+ litre surge tank.

**Ghetto-AW11** · 04-10-2006, 03:06 PM

My walbro 255l does exactly what you guys describe. Its fine for a short drive, but anything like 20-2 hours it will start to whine its arse off. Same with my mates VL. But, the exhaust is 10times louder and grumpy, so it doesnt really matter.

**TopSecret** · 05-10-2006, 09:24 AM

My VL pump gets noisy once the car has been in the sun for a while, just like what you are describing with your pump. Sounds much the same as when the pump is beginning to run dry. Nothing to be concerned about, everyone elses does the same.

**sbyder** · 06-10-2006, 03:11 AM

no worries thanks very much

I have checked the voltage when it started to make the noise last night and it all looks fine. Charging at around 14v constantly.

Might take it out to clean the strainer anyway.

Thanks peoples!
Ben

**sbyder** · 06-10-2006, 10:42 PM

Found the issue!!!

The alternator is charging the voltage up to 16Voltz!!!

Tonight the pump started to go crazy again, so i jumped out and checked the pump connections for voltage, it varied from 14Voltz and at one point jumped up to 16Voltz!

I thought it might be the pump itself trying to suck up more power, but i confirmed the voltage on the battery which was jumping up to 15.8-16Voltz as well.

Im assuming the regulator in the alternator is causing the issue. Anyone had this happen to them?

Ben

**TTMX83** · 08-10-2006, 08:50 PM

I have the same Walbro in my Cressida and it too, on a hot day or after a good fang, starts to get louder/more high pitched, no idea why, but it still supplies enough fuel at all times.

Cheers Brad.