RPM Fluctuation

[TimW]

For several weeks, after about 10 minutes of sawing, my rpm fluctuates about 30-40 rpm, while in the cut. While this is happening, I notice the fuel level in the fuel water separator bowl is fluctuating right at the bottom of the metal ring of the fuel/water separator filter.  At idle, the fuel level fluctuates right above the bottom metal ring of the fuel/water separator filter.

I have changed the fuel filter, the fuel/water separator filter, and took the tank off and turned it upside down to drain the tank.  Today, I removed the hose from the tank to the fuel/water separator and took the filter out and blew out the line.  I noticed no obstruction.  I pulled the inlet standpipe in the tank out and blew it out.

After all this, I pumped up the fuel/water separator filter bowl full with the inline squeeze bulb.  I ran the Yanmar at idle and the fuel level is the same as above.  I will try sawing some ERC tomorrow, my first.  Hopefully, my rpm will stay constant.

My question, while sawing, does your diesel's fuel/water separator filter fuel level stay above the clear bowl, like the whole separator is fuel of fuel, or is the fuel level low enough to see it fluctuating near the bottom of the filter?
hugs,  Brandi

[Southside]

Sounds like you might have an air leak in the system, small enough that at idle it's not having an impact, but under load it shows up.  

[Crossroads]

A couple areas I'd look. As mentioned, air leak. Fuel pump, air filter. That being said, I'll be the first to admit, I'm not much of a diesel mechanic. 

[TimW]

A couple areas I'd look. As mentioned, air leak. Fuel pump, air filter. That being said, I'll be the first to admit, I'm not much of a diesel mechanic.
 8

I am leaning to air leak.  Could be the squeeze bulb.  Air filter was cleaned 8 hours back.
hugs,  Brandi

[barbender]

I've had air leaks at the tank connections before. 

[GAB]

What you describe I solved by changing the squeeze bulb 2 years ago.
GAB

[TimW]

Changed the sqeeze bulb and hoses yesterday. No help.  Got a new o ring from Yanmar for the water/fuel separator bowl.  No help.  Took the line off at the tank and turned the key to the right, but not far enough to start to turn on the electric pump.  Almost no vacuum.  I reconnected that line.  Then disconnected the line just down from the separator.  Turned on the key and the same amount of vacuum was present.  Pump sounds awful also.  Went in and sent an email to Dennis @ WM to order me a new electric pump and put it on my card on file.  Asked him to email price and availability so I would know when I woke up.  Pump is $275 and coming straight from the vendor.

Dennis then asked me if I put a hose on the pump inlet and put it in a fuel can and put a hose on the pump outlet and hold it as high as the fuel filter.  I did that this evening and the pump will pump out about a foot, but pumps in spurts.  The spurts are in syn. with the loud ticks (think loud alarm clock) from the pump.  Pumps suppose to purr.

So I am down waiting on a fuel pump.
hugs,  Brandi

[barbender]

Bummer, sorry to hear that.

[ladylake]

  
I use a Carter P60430 In-Line Electric Fuel Pump on my Isuzu diesel which most times last for years  Can be bought on fleebay for under $40.  This is a rotary type pump..  Those pulse type don't last at all.  Steve

[TimW]

 
I use a Carter P60430 In-Line Electric Fuel Pump on my Isuzu diesel which most times last for years  Can be bought on fleebay for under $40.  This is a rotary type pump..  Those pulse type don't last at all.  Steve

I thought about going aftermarket.  But I want to keep the mill all original.  I don't mind the price if it gets me back sawing.  It really ticks me off when I have to jury rig, uh I mean engineer,  something to get an expensive piece of equipment running.
hugs,  Brandi

[barbender]

If it was under warranty, I would be got the original but if it wasn't and didn't involve a ton of retrofit work, I would've went aftermarket in a hot second.

[ladylake]

 If the original is a pulse type pump it will keep going out. Steve

[TimW]

If the original is a pulse type pump it will keep going out. Steve

I gather the pump you described in post #8 above keeps going out also.  As it last "most" times for years.  My pump lasted for years. Woodmizer's engine guru did say it is the first time he saw this pump go out.
hugs,  Brandi

[TimW]

If it was under warranty, I would be got the original but if it wasn't and didn't involve a ton of retrofit work, I would've went aftermarket in a hot second.

Years ago, I would have to go with cheap aftermarket.   But now I am blessed where I can buy the correct part when I can find it.  I like to keep everything neat and original.  I don't like splicing in anything unless I have too.
hugs,  Brandi

[customsawyer]

If the original is a pulse type pump it will keep going out. Steve

Not disagreeing with you but I have a Yanmar engine on one of my mills with over 10000 hours on it and it still has the original fuel pump. Maybe I've been lucky.

[ladylake]

 I've never had any luck with the pulse type. they last 2 or 3 months on my mill, 3 different ones then went to the Carter rotary pump.. Maybe it vibrates more than some ruining them.  Steve

[KirkD]

I've never had any luck with the pulse type. they last 2 or 3 months on my mill, 3 different ones then went to the Carter rotary pump.. Maybe it vibrates more than some ruining them.  Steve

Yes get a Carter that is Marine rated for gas or diesel. Will cost you about $70.00 on Amazon.

[TimW]

Thursday, the pump arrived.  What a relief.  I sawed 1x3 ERC baseboard yesterday with no rpm fluctuations.  I trashed the old pump, after I cut the pigtail off.  Now I got a Yanmar connector I can install on an aftermarket pump, if it goes out like Ladylake says those style pumps do.
hugs,  Brandi

[TimW]

Looks like that Woodmizer $$$ pump is going out.  I ordered a  Carter P60430 from Amazon.
Lately, sometimes it would not hit sawing rpm or idle rpm.  Would engage and dis engage auto clutch or turn the key off and back on to get to the right rpm.  Now, I can't maintain sawing rpm and noticed the fuel water separator filter housing is not full of fuel when engaging the autoclutch.
hugs,   Brandi

[ladylake]

 I think the Carter pump I have  on my mill is over 5 years old now and maybe 4500 hours.  Try and mount it off the engine where it doesn't vibrate as much. Mine is behind the engine on the saw frame.  Steve

[TimW]

I think the Carter pump I have  on my mill is over 5 years old now and maybe 4500 hours.  Try and mount it off the engine where it doesn't vibrate as much. Mine is behind the engine on the saw frame.  Steve

I'm not going with the Carter pump.  I bought a Edlebrock 17302 pump in town today.  My mill has the pump mounted on the mast. The Carter pump has one of the hose nipples way too big.
The Carter pump ($33) doesn't have any wires, just spade connectors sticking out, too close to the hose nipple for my tastes.
My local Yanmar specialist says max psi I need is 7psi.
        hugs,  Brandi

[ladylake]

  Thats a rotary vane pump, should work good.  The spade terminals on the Carter are not a problem.  Steve

[TimW]

 Thats a rotary vane pump, should work good.  The spade terminals on the Carter are not a problem.  Steve

That is why I bought it.  That and the fact it was in town.
hugs,  Brandi