no oil pressure reading

[frogpond]

Working on my engine yesterday getting close to firing it up needed to prime engine put oil gauge on and turned it over to my surprise and disappointment zero pressure is there a chance that the oil pump pick up tube came off? as I can't find a good diagram of this component not sure how it's attached. This is the only idea of why no oil coming through I was thinking of removing oil relieve valve housing (for some reason I don't have a filter on this '68 model) and squirting some oil down the hole in the block to prime pump but I'm sure that's really not necessary. anybody have any other suggestion or test. Regards, Paul

[WizardIII]

You say 'turned it over' so I will guess that you didn't actually have it running. Possibly not enough rpm to register oil pressure. The book says even the red light could be on with rpm below 1000. You could also back off the oil filter adapter cap a bit and then turn it over to see if any oil is being pumped. Hope that helps.
Steve

[frogpond]

Hi Steve, No running just turning over with plugs out this engine has very little wear as compression right were it needs to be. I will try your suggestion loosening oil filter cap. I think the oil pump needs to be primed for positive intake of oil is cavitating?.

[WizardIII]

I guess you could back off the oil pressure gauge also just to see if any oil is being pumped. I'm not sure what you meant about cavitating and I'm not aware that the oil pump needs to be primed. I bought my Bearcat that had been sitting for quite a while and it fired right up and pumped oil just fine.
Steve

[jhomeist]

I agree with Wizard's comments about just turning the engine over versus actually running it. Another option to check pressure is to remove the oil pressure sender (maybe that is where your gage is?) and look for an oil stream at that port. It is a smaller port than for the oil filter, so might not be so messy.

If you don't get pressure when actually running, you need to think about the pump/pickup. Has the engine been apart? The oil pickup from the oil sump in the leg is a tube that slips up into a port in the oil pump housing. That assembly is sealed by an O-ring in a gland on the pickup tube. That seal might be bad, or the housing port for the pickup tube could be split (I am told), but probably only if the pickup tube was removed from the pump housing. I had to remove my crankcase cover which involves pulling the power head, and the pickup tube was dislodged from the pump in the process. I had a difficult time getting it re-sealed when re-assembling it. While that seal was bad, I did get some oil dribbling from the oil pressure sender port when run briefly, so it was a bit confusing whether there was pressure or not, without a gage. I think you are looking for a decent stream of oil squirting from the sender port or the filter port.

[Super Sportster]

Everyone of mine, almost all have been sitting many years, I have done exactly this, cranked them over with the plugs out and they all have built up about 35lbs of oil pressure before I actually started them. Yes the oil pickup is just pushed into the oil pump with tight fitting o-ring, it's actually a "squared ring". I'd have to look to see if there is enough room for the pickup tube to fall off? I wonder if you could go through the oil level hole with a camera and check, I'll have to try that. Could the o-ring dried out and cracked giving it a place to suck air? Stuck relief valve?

[frogpond]

Thanks everybody that gives me some ideas might stop at Harbor freight and pickup one of those mini camera. I cleaned the relief valve it was all fine I think the pickup tube separated from pump the motor has been wrestled around a bit. It would shock me if they didn't have a bolt to hold that pickup tube in place I mean what a weak link!. Engine looks like it has never disassembled. UPDATE: Looking at this crosscut image it doesn't look like it can come apart very easy. What's next? Paul

[davriker]

I have a case of NOS Wix filters if you want to run one. I'm not generous enough to give for free, but don't need to make a killing either Private message me if interested.
I doubt the oil pickup tube came off, and pulling the power head to check would be about my last resort. Pull the plugs, spray some light oil in the cylinders, crank it over and give it time for the oil pressure to come up.
Dave

[jhomeist]

I agree that unless the engine was apart and the pickup tube was removed and replaced, it is unlikely that the pickup tube seal is the problem. That's why I asked whether the engine had been apart.

My Bearcat is one that never had an oil filter. I haven't added one, just change the oil frequently. What is the consensus? Do folks think one should be added? It seems like a good idea to me, but I don't know Homelite's reasoning for not having one, or if they had a downside and that's why they were omitted. Is it a special hard-to-find filter, or readily available?
Jon

[WizardIII]

I think most later models came with the adapter cap in place of a filter. Who knows why? Cost cutting? I added one to mine because it just makes sense. If nothing else I get a bit more oil in the motor. It looks like Dave has the Wix (24104) although the Napa 4104 works but you gotta tighten that puppy down pretty good. If you look for it don't be surprised if it is listed as a fuel filter.
Steve

[Super Sportster]

I think most later models came with the adapter cap in place of a filter. Who knows why? Cost cutting? I added one to mine because it just makes sense. If nothing else I get a bit more oil in the motor. It looks like Dave has the Wix (24104) although the Napa 4104 works but you gotta tighten that puppy down pretty good. If you look for it don't be surprised if it is listed as a fuel filter.
Steve

The story of the oil filter deletion goes, when Dick Fisher bought out the outboard division of Homelite and making updates to improve the engine his thoughts were there is no dust on the water therefore he felt there was no need for the oil filter. Personally I agree with you, it makes sense to have one. For the cost it's just extra insurance. The best update he did was the seats and valves making this engine capable if running unleaded fuel without modification, the "A" and "F" blocks. Done yrs earlier than unleaded was on the market. If my memory is clear from my gas jockey days Arco Clear unleaded was first on the market around 1971.

As far as priming the engine with the oil pump, I do all engines as described. My old Honda 250/305's I kick through with one corner head nut loose as the oil travels up this stud to the head. As soon as it starts leaking, I tighten it, put in the plugs and start it. I bring this up because one of these I rode briefly before it sat about 6yrs before completing a restoration.
When I went to start it I attempted to prime it, kicked my brains out and nothing! I knew it worked before so I went ahead and started it with the head nut loosened, got oil shortly after it was running. One of the few I had trouble priming.

I would probably start this engine, I would lay it on it's back, lift the lower unit end up and get the oil out of the sump into the pan coating as much of the crank and rods as possible then stand it back up and go for it.

[frogpond]

Just to let everyone know my oil pressure came up lifted engine upside down to lube rod bearing and everything else. After turn it over getting it to start a couple times the oil pressure is right were it should be. Thanks everyone who helped with advice. Paul