95 Bonn 3800 II oil pump

[Paintjar]

Has anyone done this job? I am having pressure issues. When its cold gauge is above 40 and all is well. After it reaches 200 the pressure come down to less than 40 and when it idles it just touches the red. Sometime triggering the alert off and on briefly. Mainly when I stop and the idle comes down. I replaced the filter and it starts out fine, again until the engine reaches operating temp. I hear a little clickity clack sound at idle and the gauge needle seems to move with it. The GM manual talks about many things. One is the filter adapter has a spring and valve in there. That looks easy enough to pull, clean and inspect the spring tension. My question is ,What are the signs of a pump going out? If anyone has had this issue please give me some pointers as to where to go first. Thanks

[96 SSEi]

HI, if the pump isn't working well, I assume the top end will be starved for oil, pull the rocker covers and check them.

[Paintjar]

Thanks for the tip. I can not see by the diagrams how it will fail completely. The clicking sound makes me think that is going bad. With rpms that goes away. The fact that it drops off after the engine warms makes me wonder. Is it the reason the oil thins out with the heat or something expands from the heat and causes a leak. When I changed the filter I did notice a leak after the filter on the frame near that cooler. Kind of hard to see lying underneath. I will have to get it up on the stands to be able to get a better look. I have not started on this yet as the weather is still crap, woke up to a little snow today. Warms up this week and I will start with the filter adapter I am under cover but a little chilly. Later this week it warms up here in VA. Thanks for your input.

[96 SSEi]

NP....what grade of oil are you running? 10w 40 is specified I believe I run it all year round with no issues yet.

[michtom]

Before doing anything else, you should put a gauge on it to verify any problems as the sensor could be wrong.

[Paintjar]

This engine calls for 10-30. Got under there and saw drips of oil. Pulled the wheel and covers for easy access to oil filter adapter. Noticed what looked like the way the wind blows coming from that unit. Decided to start and watch after cleaning oil from everything. Engine start and pressure is above 40 mark on gauge. Took a look and found oil was coming from pressure switch where the plastic housing attaches to the metal. Coming out slow but enuff to pull it and replace. Could be after engine gets hot comes out faster and pressure gauge can not read correct pressure. Will replace switch and post the outcome. Thanks Note: The quality of the oem appears to be faulty, the new one has a seal of some sort between the plastic and the metal.

[cjski]

The oil pump is in the timing cover housing the hardest is getting harmonic balancer off not that hard at all get info from auto zone repair help ,for procedure

[Paintjar]

May have to go there. Oil pressure still drops off when engine get warmed up. It sets off the alarm every time I stop. I recently had put AC plugs in replace of NGK and changed fuel after running 93 from 1993 to present, to 87. After about 10 tanks, fuel mileage dropped off from 25 to 20. Maybe the idle is too low. If I just touch the throttle it comes up. The tach is below 1000 at idle. I think I am going to change a few things before I dive in the motor. Does anyone know if the oil pump makes any noises when bad? Thanks for ideas.