Another Oil Pressure problem!

[RonG]

Hi,
had a number of oil pressure problems last season along with alarms. This year after an oil change and replaced both the oil sensor/sender the oil pressure has been great running steady at between 40 and 50 psi at all rpms.

Today saw something very strange. When i punched the throttle to speed up saw the oil pressure drop to zero and bounce back. On the way out it did it only once. On the way back it kept happening. Throttle up and the pressure tanked and throttle back and the pressure popped back to 40. Throttled very slowly and the pressure stayed at 40. If i hit it hard it would drop like a rock. Ok starting to repeat myself now so will stop....anyone else experience this or have any ideas?

Thanks,
Ron

 

[Quint4]

My port side 350 mag shows erratic oil pressure over 2500 rpm. Gonna swap the oil sender tomorrow. I will be watching this thread.

I really hope I do not have an oil pump problem.

 

[2000SEARAY280SS]

might want to check the oil level it could be low and sloshing away from the pick up on hard starts but this is probably a stretch since i think the pickup is in the rear. my psi has been running around 25 at idle this year for some reason on both engines goes up with throttle up.

 

[RonG]

might want to check the oil level it could be low and sloshing away from the pick up on hard starts but this is probably a stretch since i think the pickup is in the rear. my psi has been running around 25 at idle this year for some reason on both engines goes up with throttle up.

Thanks...I checked the oil level multiple times and it looked like it was down about a half quart. I wouldn't think that would cause this. Even if it was down a full quart I would be surprised. More that that and maybe that could be the cause....

 

[RonG]

My port side 350 mag shows erratic oil pressure over 2500 rpm. Gonna swap the oil sender tomorrow. I will be watching this thread.

I really hope I do not have an oil pump problem.

Quint, did you swap the sender? My mechanic suggested I try three things in this order. check the oil level again, check the sender and dash connections, screw in an oil gauge at the sender location and see if it is still erratic. Let me know how your issue turns out.

 

[Mike Blake]

Try Auto zone and see if they will loan you a mechanical gauge. You put that instead of the electrical gauge That will tell you all.

 

[Mike Blake]

What marina is that I'm from Boston years ago.

 

[Quint4]

I ordered a new sender ($29). Much easier than unbolting the floor section over my starboard engine to access the sender for the swap.

I will report back when I install the new sender.

http://www.iboats.com/mall/partfind...gd_poid=111883&gd_row=50&session_id=620830359

 

[RonG]

What marina is that I'm from Boston years ago.

marina bay in quincy

 

[RonG]

I ordered a new sender ($29). Much easier than unbolting the floor section over my starboard engine to access the sender for the swap.

I will report back when I install the new sender.

http://www.iboats.com/mall/partfind...gd_poid=111883&gd_row=50&session_id=620830359

BTW did you also get an alarm when the pressure gauge was erratic or didn't it get low enough?

 

[Quint4]

No alarm.....I suppose it did not dip low enough to trigger?

 

[RonG]

Update - pulled the connection from the sender....cleaned it and crimped it a bit to make the connection tighter and the problem went away. Will keep an eye on it to see if that did it for sure. I'm feeling pretty confident about it though because we were able to replicate the situation consistently but after cleaning and crimping it did not happen again.

 

[RonG]

No alarm.....I suppose it did not dip low enough to trigger?

Since they are two separate circuits that could mean that you don't really have an oil pressure problem and is just the sender since you didn't have an alarm.

 

[Quint4]

Still waiting on my sender to show up. Just bought an oil pressure test kit and heading to the boat shortly to get some "real" numbers.

Glad you found your problem. I will re-check my sender connection.

 

[Quint4]

Arrived at the boat with oil pressure test kit ( $25....harbor freight). Took her out on the lake and problem was still there. Removed sender wire and crimped the connector a bit.......problem fixed!

Ran it up to 4000 rpm a few times....gauge worked perfectly.

The connection was just not good enough. Added a bit of dielectric grease also.

I guess I will keep the oil sender and oil pressure kit for future use.

 

[RonG]

Arrived at the boat with oil pressure test kit ( $25....harbor freight). Took her out on the lake and problem was still there. Removed sender wire and crimped the connector a bit.......problem fixed!

Ran it up to 4000 rpm a few times....gauge worked perfectly.

The connection was just not good enough. Added a bit of dielectric grease also.

I guess I will keep the oil sender and oil pressure kit for future use.

Good deal! Glad that worked. Nice when they are simple fixes. I'm going to pick up one of those pressure test kits at HF which by the way has become my favorite hangout these days.

 

[Quint4]

By the way......thanks for your helpful advice!