450 STAIGHT oil pressure issue

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cordlesscarpenter
1010 crawler
1010 crawler
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Location: Southeast Indiana

450 STAIGHT oil pressure issue

Post by cordlesscarpenter » Thu Sep 26, 2019 4:14 pm

Genrts, back again...

I have a mid-60's 450 straight, crawler loader, diesel that is giving me uncomfortable oil pressure readings. When I start her up, and run her at "hi idle"for warm up, she is reading right around 40 on the gauge but after she fully warms up and I've been running her for half an hour or so at operating speed, she drops to about 20. After she's warm, if I bring her to idle speed, the pressure drops to 0 so I have to shut her down immediately.

Nothing sounds bad, she purrs like a kitten and never lets me down but the pressure readings I am seeing have me concerned.

When I got the machine, it had a bad oil sending unit and I am the kinda guy that needs to see my oil pressure so instead if buying a new oil sending unit for the dummy electronic gauge, I installed a mechanical gauge. I also changed the oil from whatever the previous owner was running to a synthetic 15w-40 and at that point the oil pressure would get up to around 30-35 at start up and drop progressively to 20 once warmed up. Once I started seeing the drop in pressure I thought I may need to switch viscosity from synthetic 15w-40 to a conventional straight 30 weight, thinking the the synthetic dual viscosity oil was getting too thin at operating temp and maybe the pump was loosing prime. So I changed out the oil to 30 weight and it helped but is still dropping pressure once warmed up to 20 and down to 0 when placed at idle before shut down.

I'm thinking it could be a clogged pick-up or possibly worn gears????

Thoughts???

Thanks!

B Town
350 crawler
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Location: Western Iowa

Re: 450 STAIGHT oil pressure issue

Post by B Town » Thu Sep 26, 2019 5:04 pm

My guess is a aged oil pump and ever increasing bearing gaps in the crank, rods, cam and balancing shafts. It sounds like you have an otherwise good engine. If you are certain your oil pressure reading is accurate, you could consider an underhaul. It takes 10-12# of pressure to float the rotating masses. The underhaul would address oil pump and the rods and crank bearings. I assume you machine doesn’t have a turbo. You could consider a ZDDP addictive or a Lucas addictive. These are pretty short sighted solutions IMHO.
Best regards, Bruce

cordlesscarpenter
1010 crawler
1010 crawler
Posts: 265
Joined: Mon Jun 17, 2019 3:36 pm
Location: Southeast Indiana

Re: 450 STAIGHT oil pressure issue

Post by cordlesscarpenter » Thu Sep 26, 2019 7:24 pm

Sorry, I forgot to mention that the engine was supposedly re-built in 2012, so only 7 years ago and was told it sat in the barn for the better part of 2 of those years... otherwise it has only seen farm use. The first thing I'm going to address in the morning is to disconnect the gauge and and fill the inlet line, to make sure there is no air in the line and effectively "prime" the gauge. At least then I'll know the gauge is reading correctly. Next step would be to drop the pan and see if I can see anything noticeably wonky and go from there.

B Town
350 crawler
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Location: Western Iowa

Re: 450 STAIGHT oil pressure issue

Post by B Town » Thu Sep 26, 2019 7:47 pm

While the pan is off, consider using some plasti-gauge in at least one rod and one crank bearing.

cordlesscarpenter
1010 crawler
1010 crawler
Posts: 265
Joined: Mon Jun 17, 2019 3:36 pm
Location: Southeast Indiana

Re: 450 STAIGHT oil pressure issue

Post by cordlesscarpenter » Fri Sep 27, 2019 6:47 am

Is there an oil pressure relief valve on these engines? Just thinking perhaps it sticks open? Looking into the plastigauge.

Jim B
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Re: 450 STAIGHT oil pressure issue

Post by Jim B » Fri Sep 27, 2019 4:13 pm

There is an oil pressure regulating valve. It should be accessed through a port in the right side of the front cover. You have posted in the past that you have a 450 service manual. You should find information on oil system, oil pressure checks, the pressure relief valve, and adjusting it, in the engine lubrication section of your service manual. Rather than trying to post a duplicate what is in the manual, I think it will be better if you read what is in the manual to start with.

Besides main and rod bearings the cam bearings can be a cause of low oil pressure. Replacing those sometimes get skipped when rebuilds are done. There is not much way to check them short of a teardown.

If you have another gauge I would try it as well. A lot of new gauges are poor quality and not accurate over the full scale I've found. Usually the smaller the scale the better, you can see lower pressures easier. A 60 psi gauge will show readings better than a 100 psi gauge of the same physical size if the range is spread over the same area of the gauge face. JMHO

cordlesscarpenter
1010 crawler
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Joined: Mon Jun 17, 2019 3:36 pm
Location: Southeast Indiana

Re: 450 STAIGHT oil pressure issue

Post by cordlesscarpenter » Sat Sep 28, 2019 7:56 am

Thanks Jim, two great ideas.

I plan on looking in the manual this morning for solutions.

I also plan on buying an independent high pressure gauge for hydraulics anyhow so I'll plan to pick up a 60 psi gauge while I'm at it. Any recommendations on where to get these gauges?

If adjustments and or a good gauge doesn't solve my concerns, the plan is to do an underhaul as well as replace the oil pump.

I primed the gauge line yesterday before cutting some new trails and the pressure did stabilize much better but still dropped off to about 20-25 psi at operating speed after about 30-45 minutes of work.

Jim B
350 crawler
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Re: 450 STAIGHT oil pressure issue

Post by Jim B » Sat Sep 28, 2019 8:42 am

I don't know what is available for sources in your area. For the hydraulic gauge you can check your local hydraulic shop or go to eBay (or Amazon) and get a liquid filled hydraulic gauge there. I'd get at least a 3000 psi gauge for hydraulics, I think the JD manual calls for a 5000 psi gauge. 1/4" NPT, bottom mount style will work. You can get various adapters from 1/4 NPT to fit different ports. Always get hydraulic adapters as the hydraulic pressures will exceed the rating of hardware store fittings and splitting a fitting can cause injury. I have high pressure gauges but got a couple liquid filled 300 psi gauges for checking clutch pressures on some equipment from eBay, those work fine. You shouldn't need calibrated gauges for your own use.

For an engine oil pressure gauge; send Lavoy an email at postmaster@jdcrawlers.com and see what he has for oil pressure gauges (he might have a hydraulic gauge as well). One made like a Stewart Warner # M-82322 would be good. It reads 5 to 80 psi and is spread over almost the complete circumference of the gauge face, which should give a good visual in the lower ranges. To me the more spread out the numbers are the better it is to tell the true reading.

cordlesscarpenter
1010 crawler
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Posts: 265
Joined: Mon Jun 17, 2019 3:36 pm
Location: Southeast Indiana

Re: 450 STAIGHT oil pressure issue

Post by cordlesscarpenter » Sat Sep 28, 2019 6:38 pm

Thanks for the 411 on gauges. I'll definitely give levy a shout first

I read the manual, found the oil pressure reg valve and it had no shims. Added a proper sized washer of .060 thickness (little less than 2 of the original shim thicknesses (says you can use a max of 4 (.036 shims)). It helped the pressure for sure but it is still dropping after 30 minutes or so down to about 25 now. I know this is only a bandaid fix and will do an oil pump swap and underhaul as soon as the current project is over and we head into the winter.

Daisy (my crawler's name) sprung a leak today on one of the bucket's had hoses, will remove tomorrow and get one made Monday.

On another note, I should be finalizing the purchase of the backhoe 450 crawler/loader (with 4-in-1 bucket) I mentioned in another thread this coming week! I'll have my hands full with her ALL winter and probably most of the spring. :-)

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Jason37756
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Location: Tennessee

Re: 450 STAIGHT oil pressure issue

Post by Jason37756 » Sat Sep 28, 2019 8:01 pm

Lots of good info here....no oil pressure is scary. To think some equipment doesn't even have an oil pressure guage.

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