Oil Pressure-Bugeye Sprite

Hi y'all
I am new to the forum and jump in straight away with a question. I have a 1959 Bugeye Sprite which has been modified with a 1275cc engine and upgraded front suspension and disc brakes. While driving this weekend I noticed the oil pressure dropped to anywhere between zero and 20lbs, while occassionally jumping up to 40lbs.
Is there a simple way to check to see if it is a faulty gauge/switch or pump failure? The car is in the garage until I get this sorted out!
Thanks
Tony

Buy a cheap gauge from autozone and compare. 20 lbs fluctuation is common, but going less than 20 psi is not so good.

It's very unusual for an A-series, especially a 1275 to have less than 40-45 PSI, even at idle. You could just have a faulty pressure relief valve (plug below oil feed between block and oil filter), but you should look into it since it could also indicate a bad bearing or weak oil pump. Rule of thumb, 10PSI / 1000 RPM, so anything less that 20- 30 PSI is cause for concern.

I had a strange incident this weekend. I was out in my 1960 sprite (948, non working Tach) and after an hour I came to a stop and started smelling fuel and noticed Oil Pressure at about 10PSI. It's normally at 25-30 at Idle. As soon a I accelerated it went into the normal 40ish range. I came to another red light and PSI dropped like a rock again.

Got the car home and popped the hood to notice a major fuel leak coming from the hose that connects the two Carb Float Bowls together. A new hose is on order from VB, but my assumption is that lack of fuel caused extremely low RPM's at idle which hampered the oil pump and therefor low pressure. I hope I am right and that there is not a greater Oil pressure issue at hand. Everyone keep your fingers crossed.

But Tony, I am sure you and I both (as newbies) had that same feeling of our heart's dropping along with the Oil Pressure!!!

That may be possible but I think not likely. Dropping the idle that much would be more likely to stall it completely. Even if not you certainly would have noticed it. Fix the leak and try again but be prepared for a deeper investigation.

I've had this happen to me, due to low rpms

With the second problem, be sure you don't have a ripped fuel pump diaphragm. The 948 uses a mechanical fuel pump. If the diaphragm rips, it may allow fuel to enter the engine sump....causing fuel smells and low oil pressure.

With the original poster's question, I would do as Trevor has suggested. Buy an inexpensive oil pressure gauge. Most of these gauges have a 1/4-NPT thread, so you can thread the gauge directly into the engine block, eliminating the line that normally goes from the engine to the gauge.

Thanks to all for the advise. I will get cracking this weekend and see if I can track it down.
Tony

Just got my sleeves rolled up. Guess what? Low oil pressure=low oil level!
Just needed to top up the oil and make sure I keep an eye on it in future.
Thanks

As for my issue - my oil was a little low. I topped it off, and replaced the Carb Hose and am now without issue. I have an electronic fuel pump so am ok on the diaphragm issue, but now I am constantly monitoring fluid drips and leaks by changing my cardboard out after every drive to inspect. Since I dont have jackstands yet, this is the best way for me to monitor locations of drips without getting under there. It would be great if someone had a graphic that showed the footprint of the car with various spots called out indicating what a leak could be from based on location of drip.

oil leaks are sort of like a water leak in a house the drip point could be "miles" from the source.. unless it's coming in buckets.. live with it or... do a rebuild including a line bore with a new rear plate... thinking, a cheap fix is the valve cover gasket.. Might try that and since it is at the top of the chain, you can certainly see the results conclusivly.

other issue is internal pressure build up..not to be overlooked..Make sure you have an operational PVC set up as in OEM or one that works.. Not doing so can cause leaks just about everywhere on the engine!

Concur, when I got Bugsy home he had the crankcase vent plugged and the other end of the vacumn line plugged with a 3" 3/8 extension bar crammed in the end of the hose. Engine ran but pumped oil out the rear seal like you would not believe. I thought I bought the Exxon Valdez.

Replumbing and following the pics in the MOSS manual got correct negative pressure in crankcase, rear seal leak slowed to a single drip when I stop and 3-4 other small drips that is a case of Bugsy marking his territory. Engine needs a valve job and rings I know, but seems to run fine, still has lots of pep, starts too quickly since carbs were worked on as in let it crank and crank and don't pull out the choke so you can get some oil pressure built up, is not smoking, and 20W50 can be had for a whole lot less than a rebuild. For the amount of driving most of us do with these cars unless it's really smoking or making nasty noises get in and drive. Thse engines have taken a tremendous amount of abuse over the years and with a little care and maintenance will continue to be a sweet little powerplant. Get in, have fun, and drive it like you stole it as Frank used to say.