Nevyn Posted March 28, 2016 Author Share Posted March 28, 2016 Bad pump or trashed bearings. Whats the best way to test the pump? Whats involved in testing the pickup? Link to comment Share on other sites More sharing options...
Cuong Nguyen Posted March 28, 2016 Share Posted March 28, 2016 remove pump, make a tool that will fit in the pump keyway to spin the pump using a drill. sit pump in tube of oil. let drill spin, and see if oil pumps out. It's late and I cant think of anything else at the moment. 1 Link to comment Share on other sites More sharing options...
Nevyn Posted March 28, 2016 Author Share Posted March 28, 2016 remove pump, make a tool that will fit in the pump keyway to spin the pump using a drill. sit pump in tube of oil. let drill spin, and see if oil pumps out. It's late and I cant think of anything else at the moment. Thanks for that Cuong.....I will do that tomorrow...I have a feeling it won't be the problem though as the pump came off the engine I took out...but best to check everything first...... not looking forward to having to change the bearings with the engine in the Pathfinder still Link to comment Share on other sites More sharing options...
Slartibartfast Posted March 28, 2016 Share Posted March 28, 2016 The LC section of the service manual has you check pump clearances with a feeler gauge, but the stick-it-in-a-bucket-of-oil test is probably what I'd do too. Looking at the exploded diagram, though, I see that there's a gasket that goes in between the pickup and the pump. Are you sure that gasket went in properly? If that's missing/torn/seated wrong it could be letting the pump suck air instead of oil. Link to comment Share on other sites More sharing options...
Nevyn Posted March 28, 2016 Author Share Posted March 28, 2016 The LC section of the service manual has you check pump clearances with a feeler gauge, but the stick-it-in-a-bucket-of-oil test is probably what I'd do too. Looking at the exploded diagram, though, I see that there's a gasket that goes in between the pickup and the pump. Are you sure that gasket went in properly? If that's missing/torn/seated wrong it could be letting the pump suck air instead of oil. I have had a look in the manual, hopefully I will be able to put it to good use...... as for the gasket, I never pulled the pump apart...so the only gasket is what will go between the pump and the timing cover....that had a new gasket, but I will make a new one from some gasket paper.....its a bit thinker than the bought one, but should still work ok. Link to comment Share on other sites More sharing options...
Cuong Nguyen Posted March 28, 2016 Share Posted March 28, 2016 The LC section of the service manual has you check pump clearances with a feeler gauge, but the stick-it-in-a-bucket-of-oil test is probably what I'd do too. Looking at the exploded diagram, though, I see that there's a gasket that goes in between the pickup and the pump. Are you sure that gasket went in properly? If that's missing/torn/seated wrong it could be letting the pump suck air instead of oil.I have never seen one fail but like they say, never say never. Sent from my SAMSUNG-SM-N920A using Tapatalk Link to comment Share on other sites More sharing options...
Nevyn Posted March 28, 2016 Author Share Posted March 28, 2016 the one positive coming out of all this is I am learning more n more about the engine, running gear, and suspension Link to comment Share on other sites More sharing options...
Nevyn Posted March 29, 2016 Author Share Posted March 29, 2016 tested both oil pumps today, and both are pumping fine.....back to square one.....Is it important the the pump be full of oil when put back in place? Link to comment Share on other sites More sharing options...
Cuong Nguyen Posted March 29, 2016 Share Posted March 29, 2016 It doesn't have to be full of oil. Generally on most my builds I pack it full of vaseline/petroleum jelly. Doing this you get rid of the air pocket and instant vacuum is created as the pump gear rotates. Sent from my SAMSUNG-SM-N920A using Tapatalk Link to comment Share on other sites More sharing options...
Nevyn Posted March 31, 2016 Author Share Posted March 31, 2016 that sounds like bloody good idea Coung.....will have to get some......I have been told to unbolt the pickup pipe and put an air hose in the hole and blow it threw to check for any blockages in the block, will do that today Link to comment Share on other sites More sharing options...
Nevyn Posted March 31, 2016 Author Share Posted March 31, 2016 Bad pump or trashed bearings. To help get me head around this.....How can trashed bearings affect the oil pressure? Would they be the main bearing or the rod bearings? Or both? Link to comment Share on other sites More sharing options...
Cuong Nguyen Posted March 31, 2016 Share Posted March 31, 2016 bad seal (large clearance) lowers oil pressure which could equate to poor flow. Also, if the crank bearings are bad, the oil holes in the crank could be plugged and restrict flow to the rod journals. Link to comment Share on other sites More sharing options...
Slartibartfast Posted March 31, 2016 Share Posted March 31, 2016 The oil pump just moves oil. The tight clearances of the bearings restrict how quickly oil can flow through them, and flow against restriction makes pressure. The pressure forces the oil to find every available exit (all the places it needs to go to keep the engine happy). As the bearings wear, the clearances get bigger, and the oil runs through them quicker. If the bearings wear to the point where the pump can't keep up with how much oil they're dumping, you lose oil pressure. Think of it like a compressor trying to inflate a tire that's got a nail in it (slow leak) vs a tire that's already come off the bead. I would expect the rod bearings to see the worst of it but you've got the pan off anyway, you might as well check the lot. Link to comment Share on other sites More sharing options...
Nevyn Posted March 31, 2016 Author Share Posted March 31, 2016 I can get both sets of bearings here for $110, so may as well do both while I have the sump off.....all up since I have had this engine in I'd say it had been running for around 20 minutes trying to get the oil pressure up.....how much damage would you think would have been done to the bearings?for a temporary engine its getting a lot of money spent on it Link to comment Share on other sites More sharing options...
Kingman Posted April 1, 2016 Share Posted April 1, 2016 Well the crank gets the most oil first, if any were to go it'd be the NO. 2 rod bearing since it's the last in line to get oil. If it was just idling it may not be all that bad but I'd definitely expect some wear. If you can see copper it's time for a rebuild. Um however, just throwing bearings in it isn't a good idea... the crank needs to be taken to the machine shop to be checked and polished. If you're planning on Nissan bearings, they are sold "undersized" which means the crank needs to be turned. Many aftermarket brands sell them standard size so if the crank is fine to just be polished you'll be alright there. Don't forget the plasti-gauges to measure tolerances. Link to comment Share on other sites More sharing options...
Nevyn Posted April 1, 2016 Author Share Posted April 1, 2016 As I have said, this engine is just a temp fix for now while I get the engine I took out a full rebuild....for now I just want it to get on the road and get me around for 2-3 months.One thing that was suggested to me today is to use the bearings from the original engine instead of spending money on something that I will rip out in a few months.....I would rather save me money if I can for the rebuild..... Link to comment Share on other sites More sharing options...
Kingman Posted April 1, 2016 Share Posted April 1, 2016 If they're fine run it Link to comment Share on other sites More sharing options...
Nevyn Posted April 3, 2016 Author Share Posted April 3, 2016 If they're fine run it got another week off, so will get a start on it today sometime Link to comment Share on other sites More sharing options...
Nevyn Posted April 15, 2016 Author Share Posted April 15, 2016 I seem to have the oil pressure problem fixed for now......the light isn't going off as quickly as it should, and then after idling for a while it will flicker then come back on, but if I give it a few revs the light goes back out.....now to get the front diff back in before taking it for a drive Link to comment Share on other sites More sharing options...
Nevyn Posted April 22, 2016 Author Share Posted April 22, 2016 Pathfinder is up n running....have driven it around a few times since yesterday, oil light still comes on if left idling for too long.....just needs a good wheel alignment now and should keep me on the road till the other engine is fully rebuilt Link to comment Share on other sites More sharing options...
Cuong Nguyen Posted April 22, 2016 Share Posted April 22, 2016 What weight oil are you running? Could go heavier to see if it'll help. Sent from my SAMSUNG-SM-N920A using Tapatalk Link to comment Share on other sites More sharing options...
Nevyn Posted April 23, 2016 Author Share Posted April 23, 2016 been an older engine I have always used 20-50 oil in it....I did come across a 30-60 oil about 4yrs ago and used that for awhile as I had a few leaks from the sump Link to comment Share on other sites More sharing options...
Slartibartfast Posted April 23, 2016 Share Posted April 23, 2016 Thick oil and a light foot and hopefully it'll hold until your rebuild's ready. Link to comment Share on other sites More sharing options...
Nevyn Posted April 23, 2016 Author Share Posted April 23, 2016 Thick oil and a light foot and hopefully it'll hold until your rebuild's ready. defiantly a light foot....I won't even start moving till the oil light comes on.....overall its running better than the engine that came out, but be interesting to see how it goes on a few hills where this engine use to lose a bit of power.......won't do that till I get a wheel alignment on Tuesday, after having the torsion bars and front diff out it badly needs an alignment. Link to comment Share on other sites More sharing options...
grandsonscrptcln Posted May 20, 2016 Share Posted May 20, 2016 FROM MY EXP YOUR TIMMING IS SET WRONG AND ITS A INTERFERENCE ENG YOUR VALVES ARE TOAST EVEN ONE TOOTH OFF THE MARK YOU ALINE ON THE VG30 ON OUT SIDE L3 R3 DONT SEE Y IT CHANGES I MAY BE WRONG CHECK YOUR OIL MARK ON TIMMING ALSO THEY HAVE TO BE RIGHT IF NOT YOUR DOOMED . Sent from my LGMS330 using Tapatalk Link to comment Share on other sites More sharing options...
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