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Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 30134
Experience:  Service manager and technician for all brands of engines with 40 + years of experience.
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Have Onan generator, MDKAU with Kubota engine. Exhaust

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Have Onan generator, MDKAU with Kubota engine. Exhaust gasket blew which has been changed together with exhaust temperature sensor.Replaced manifold gasket and heat exchanger gasket on reassembly. Engine won't start, fuel being delivered but no compression.

By looking at the engine parts, there is no compression release. So Compression can be tested by removing the glow plugs and using an adapter to test compression. But are the glow plugs working and heating the cylinders when glow plug is selected? HAve the valves been checked? If valve was open, on cylinders, you would have no compression.?

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Call not being completed! If you have no compression, it is a result of the cylinder itself. The only thing that determines the compression is the pistons and rings and the valves. Nothing Else will affect compression! That is why the compression needs to be checked or at least check the valves, for clearnace.

Customer: replied 1 year ago.
Was waiting for response on fone. Have checked valve operation, seems ok.On boat have no means of testing compression. Engine in good condition not done much work. Why should this suddenly occur.

did valves have clearance? If valves had clearance, then you may have cylinder damage. Could there have been water enter cylinders when the manifold was off?