Topic: Dry Engine Start-up ? First Dry-sump Experience

[RRRToolSolutions]

Guys, the 74 CB750 is back together and the wiring is getting close. This is my first rebuild of a dry sump engine. Every bike I've rebuilt in the past had a crankcase where oil was filled and checked through the dipstick hole. You "knew" oil was in the crankcase and transmission because you could see it. On the 2 strokes, you simply add oil to the start-up fuel and make sure the tranny is lubed.

I've removed the plugs, I've added about 3 quarts of Motul 10/40 and I've kicked it over several times. I don't have any oil pressure showing and the oil tank is not going down like it should. I've added one of Terry's oil coolers and I figure a good 1/2 quart for it and the filter.

I'd appreciate some suggestions on getting some oil pressure before I start it up and run it. My CB500's oil light will go out when kicking iit over, so the oil pressure should come up during a kick once primed.

Thanks,
Gordon

[Bob Wessner]

Mine had been sitting for 20+ years, so I was concerned about oil flow/pressure the first time starting it also. I removed the plugs and turned off, er.. is it on, the kill switch and cranked it with the elec. starter. The oil light went out and I was able to determine oil was reaching the top-end as well via the tappet caps.

[MRieck]

I pour 2 quarts into the oil tank and about a quart into the engine via a tappet adjuster hole to makes sure there is oil in the sump. I then prime it as Bob described.

[RRRToolSolutions]

Mike, the 1 quart through the # 1 tappet hole did the trick. The pump primed and got up to 30 psi on the starter in just a few seconds plus the oil in the tank went down telling me it was pumping fresh fluids where there hadn't been any in a long time.

Thanks,
Gordon

[MRieck]

That's great...glad I could be of service.