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Westebeke 4108 high rpm on start up

gaffman

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"I have to bleed the (1976

"I have to bleed the (1976) Westebeke 4-108 after changing fuel filters every year. The motor ran fine last Fall.

After bleeding, the motor started right away, but the motor took off. High rpm's. Loud and a little scarey. I guess it is not a "runaway diesel" because I was able to shut the motor off with the (Mechanical) fuel shut-off. Also, there is not too much motor oil in the pan.
I haven't started it again to see if it would happen again, yet.

Any ideas what would cause such an event?"
 
"Hi matt,
When you ble


"Hi matt,
When you bled fuel pump at top nut the bottom also must have turned if this goes in to far govener will loose control back it off then start engine with air cleaner off so you can starve engine to control rpm if neccessary.
Tassie.."
 
"The high rpm was most likely

"The high rpm was most likely caused by air in the fuel pump.( Unless you made adjustments to the pump by accident). It is not dangerous. Make sure that the throttle is not full open.
The Westebeke 4-108 is actually a Perkins engine.
Make sure the shut down leaver is put back in the start position if so equipped.
On the fuel injection pump you will find 2 bleed screws, 1 on the side on the bottom and 1 on the top. Open the bottom bleed screw first and pump the fuel through the system using the leaver on the fuel lift pump or electric pump whichever is fitted. When all the air has been purged out and a steady stream of fuel comes out, close it.
Open the top vent screw and repeat the procedure and close it.(sometimes it is not necessary to open the top)
Then loosen the fuel line at the fuel injector and turn the engine over using the starter until fuel spurts from the fuel lines at the injector. Then retighten the fuel lines. Now start the engine. If it surges and shuts down there still may be air in the system. Repeat the procedure over until it runs.
Do not over crank the starter longer than 15 seconds when bleeding or starting the engine. This so that the starter is not damaged.
If the rpm surges up and down just leave it until it levels out or stops. If it races out of control shut it down and get a qualified service tech to readjust the injection pump."
 
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