I recently found that I had water in one of my engines (another conversation). When I went to change the oil, the oil was the milkshake color that would be the case when water and oil mix. I heated up the engine to operating temp and drained the oil. I was using Castrol 20W 50W. When I put the new oil in, I switched to Mobil 1 syn 15W 50W, Mobil 1 oil filter m301 I think. When I started the motor, the oil pressure gauge started to rise, then went to zero and never recovered. I was expecting several oil changes to get the water out anyway, however, never got that far. I pulled the distributor and turned the oil pump with a drill to try and build pressure, nothing. I drained the engine, and filled with 5 gallons of diesel and let it sit overnight to break down any possible sludge that could have been there from the water/oil mix. The grease like sludge I found on the inside of the valve cover. I thought the oil pump might be clogged. After draining the diesel, I filled up with 20w 50w non-syn. Turned the pump with a drill, no pressure. Removed the oil pressure sending unit, and put a mechanical on it, no oil pressure. When I remove the oil filter and turn the oil pump, oil is flowing so my problem must be deeper. I was told that when you go from a mineral base oil to a synthetic and water is involved, you sometimes have instant oil GEL that clogs the engine. I am searching deeper now into the engine before my last resort, pulling the motor. Has anyone encountered this before? I need some advise. I think I will try the oil cooler next?????
Re: No Oil Pressure after oil change to Synthetic?
Does the new filter have the anti drain back valve? Did the old one? and are the oil lines into and out of the filter correct. If they were reversed and the old filter didn't have the valve , things would appear fine till you put a filter on that had one
Try cranking the engine with the filter off. The oil should enter the filter in the small holes on the outside...not the center hole.
__________________
You can never have too much horsepower or money...It's just hard to have both.
Re: No Oil Pressure after oil change to Synthetic?
I vote for reversed oil lines to the filter adaptor. In this case the pump will build resistans because the oil has no way to go. A friend burned a drill this way. Check oil lines (see above)!
Location: Omaha, Nebraska Boat on the Mighty Mo! Longest River in USA!
Posts: 1,037
Pachanga-27 Twin 502s
Re: No Oil Pressure after oil change to Synthetic?
If the lines are reversed it would not make any difference. You still will have oil pressure. Filter would just be bypassed.
I learned this lesson the hard way
This is very simple. Like previous posted, when you use a priming tool you should feel alot of resistance on the drill. The oil pump is not working or you have a hole the size of a quarter somewhere Even if you spun a bearing you would still have oil pressure.
Re: No Oil Pressure after oil change to Synthetic?
If your oil filter block off plate doesn't have a bypass, and depending on where you read your oil pressure if the lines are reversed with an anti-drainback filter it is possible to not get oil pressure in the motor. If you block off plate has a bypass, like the stock merc stuff the motor should still get oil but it would bypass the filter and oil cooler. My vote is reversed lines on the filter and no bypass in the block off plate. Your valves will ship on monday. Sorry not sooner! I have been out of town this week.
Re: No Oil Pressure after oil change to Synthetic?
Thanks for the reply's.
Wette Vette, I will look for the valves. Thanks
I never touched the oil lines, so reversing them is out of the picture, unless you are suggesting reversing them to reverse oil flow??. I just changed the oil a couple of months ago, it had about 15 hours since the last oil change, noticed the milkshake and decided to start and oil change process. It has sat for extended periods of time. I did mean 5 gallons of diesel. I never ran it with the diesel in it, just let it sit overnight to break up any possible sludge as I thought it may have plugged up the oil pump. When using the drill, it does show resistance and oil does flow to the oil filter. I am going to tackle this again tomorrow. If my memory serves me correct, I am not sure if the oil cooler is pre or post oil filter. I am hoping post as I will remove and have a radiator shop flush and clean. If that is not it, I will pull the oil line from the filter to the pump. The gel idea came from my engine builder, very reputable and someone I trust. I am not going to start the engine until I feel comfortable that I am building pressure from the drill. If all else fails, I am pulling the motor.
Re: No Oil Pressure after oil change to Synthetic?
The lines on the filter housing may be reversed. You wouldn't notice this with a drainback type of filter. If the M1 filter is a non-drainback filter the oil will not flow through if the lines are reversed. A cheap test would be to put the same type of filter on that you used before and see what happens.
I thought the oil pump might be clogged. After draining the diesel, I filled up with 20w 50w non-syn. Turned the pump with a drill, no pressure. Removed the oil pressure sending unit, and put a mechanical on it, no oil pressure. When I remove the oil filter and turn the oil pump, oil is flowing so my problem must be deeper. I was told that when you go from a mineral base oil to a synthetic and water is involved, you sometimes have instant oil GEL that clogs the engine. I am searching deeper now into the engine before my last resort, pulling the motor. Has anyone encountered this before? I need some advise. I think I will try the oil cooler next?????
Platinum Member
Gold Member
Even if you spun a bearing you would still have oil pressure.
