carl_jarrett
Member
Posting this here but also posted on The Hull Truth. More of an FYI for anyone with a similar issue as it was very frustrating for me.
Posting this because it's been a total head scratcher for me trying to figure out our issue and I've learned a few things. And hopefully Google bots crawl this post for the next person with a similar issue.
In November we were out on the water and got a low oil pressure on our port engine. I shut the engine off, checked the oil, looked for leaks etc... All seemed ok. Started the engine up again and the oil pressure was all over the place. Dropping to zero then bouncing to 40, to 80, then fully pegged (over 1,000). I figured it must be the sensor/sender.
We made it home slowly just in case at around 7kts. Started to investigate and got the service/shop manuals out for the engine which covers many versions of the 4.3 from GX to OSi etc... In the manuals it shows a pressure sender that is around 2inches in diameter with a single ring terminal connector at one end and a 1/8in NPT thread at the engine end. It shows the sender connects to a 45 adapter at the rear of the engine, near where the distributer goes I think. I ordered a Sierra version of this sender for $50.
Got to the boat, and for the life of me, I cannot find that sender on my engine. I spent a lot of time lookint, but in my particular boat (2008 Chaparral 290 Signature) there isnt a lot of room back there and I'm 6'3", couldn't find it. Today I went down with my inspection camera, not luck either. Nothing that looks or feels like the sender I bought.
Looking around the rest of the engine, I found a couple of other senders. Both on the port side of the engine, just past the most rearward exhaust port of the manifold. One is coolant temp as its attached to coolant lines. The other is right above the oil lines that connect to the remote oil filter housing. It was actually barely hand tight, and I pulled it out and some oil escaped, maybe 100ml.
Once I was able to see the part number on it, determined that its the sender/sensor/switch. It has 3 terminals and is smaller than the sender I bought. Once disconnected my boat reads 0 oil pressure and the alarm is sounding every 2 seconds. This part is 3887328 which isn't referenced anywhere in the shop manual. Also luckily, it's much easier to reach and access. Should have the part next week and hopefully all is sorted.
Anyhow, hope this helps someone else, I couldn't find this info anywhere or an image of where this bloody thing is.
Posting this because it's been a total head scratcher for me trying to figure out our issue and I've learned a few things. And hopefully Google bots crawl this post for the next person with a similar issue.
In November we were out on the water and got a low oil pressure on our port engine. I shut the engine off, checked the oil, looked for leaks etc... All seemed ok. Started the engine up again and the oil pressure was all over the place. Dropping to zero then bouncing to 40, to 80, then fully pegged (over 1,000). I figured it must be the sensor/sender.
We made it home slowly just in case at around 7kts. Started to investigate and got the service/shop manuals out for the engine which covers many versions of the 4.3 from GX to OSi etc... In the manuals it shows a pressure sender that is around 2inches in diameter with a single ring terminal connector at one end and a 1/8in NPT thread at the engine end. It shows the sender connects to a 45 adapter at the rear of the engine, near where the distributer goes I think. I ordered a Sierra version of this sender for $50.
Got to the boat, and for the life of me, I cannot find that sender on my engine. I spent a lot of time lookint, but in my particular boat (2008 Chaparral 290 Signature) there isnt a lot of room back there and I'm 6'3", couldn't find it. Today I went down with my inspection camera, not luck either. Nothing that looks or feels like the sender I bought.
Looking around the rest of the engine, I found a couple of other senders. Both on the port side of the engine, just past the most rearward exhaust port of the manifold. One is coolant temp as its attached to coolant lines. The other is right above the oil lines that connect to the remote oil filter housing. It was actually barely hand tight, and I pulled it out and some oil escaped, maybe 100ml.
Once I was able to see the part number on it, determined that its the sender/sensor/switch. It has 3 terminals and is smaller than the sender I bought. Once disconnected my boat reads 0 oil pressure and the alarm is sounding every 2 seconds. This part is 3887328 which isn't referenced anywhere in the shop manual. Also luckily, it's much easier to reach and access. Should have the part next week and hopefully all is sorted.
Anyhow, hope this helps someone else, I couldn't find this info anywhere or an image of where this bloody thing is.