OIL PRESSURE DROPS

Discussion in 'Ranchero Tech Help' started by Pookieja, Jul 23, 2018.

  1. 1965 Ranchero 66G

    1965 Ranchero 66G In Maximum Overdrive PLATINUM MEMBER

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    New cam installed without new bearings or it being line bored will bite you In the a.. .
     
  2. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Something's not jiving here--the engine was rebuilt, low miles but sat for many years, now has low pressure and garbage in the oil sample. If I didn't know any better, and if I were to be right, I'd be angry about it, because it would mean the PO screwed up the engine, and didn't tell Pookieja about any engine problems in the sale.
     
  3. ribald1

    ribald1 In Maximum Overdrive PLATINUM MEMBER

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    Brand new parts fail.
    Seen it happen bunches of times. The pin sheared on the solid roller cam on my 521 less that 300 miles after break in. Took out most of the valves, damaged some guides, damaged the ceramic coating on 5 of the pistons and 4 of the combustion chambers. Luckily it happened at 25 MPH. Had it happened during a 7000RPM pull it would have been hosed.
    Had a valve spring break on a new Eddy head within 100 miles, had rocker stud failures on several ARP heads, oil pump failing during break in, the list is long.
    The best builder is only as good as his parts, and the best parts are not perfect.
     
  4. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    You're right about that, but I'm pointing to the possibility the engine was damaged before the sale and possibly covered up. When I bought my F4TE 351W, I had the seller get it hot, then do a couple 4000 RPM pulls while I listened to it, and watched the gauges, so as to ensure that I'd have a better chance to find any problems.
     
  5. Pookieja

    Pookieja In Second Gear

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    Location:
    Indiana
    yes i know, but cold & hot give different values along with a dry/wet test. As long as all are within 10 to 15%.. And yes at this point i'm already disappointed to no end with the cost of a rebuild so soon..A few local friends think it could be the cam wasn't broke in correctly when it was rebuilt in 2008 they think possibly just a top end repair will do it . i'm hopeful but not optimistic.. At present i have my 64 wildcat on the lift and was trying to finish up front/rear drum breaks, shocks, bushings & tie rods that I've been putting off..Now this happens:(:mad:
     
  6. Pookieja

    Pookieja In Second Gear

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    Location:
    Indiana
    Yes the more i think about it I do think after the break in something went wrong and maybe they did cover it up and moved it to a big auction house for quick sale. Never the less I love the truck and will move to repair her..cant cry to much over spilt milk now, does no good.
     
  7. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    You may have to yard the engine and do a teardown, document everything, if you decide to pursue legal action.
     
  8. Pookieja

    Pookieja In Second Gear

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    Indiana
    after owning her for 5 years i didn't think i could do anything really..
     
  9. cbolt

    cbolt In Fourth Gear SILVER MEMBER

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    I wonder why the engine was rebuilt in the first place since the vehicle has so little miles on it. You are right though, water under the bridge at this point. Personally I don't purchase an old car without plans to tear the engine down and rebuild/refresh it. Peace of mind because you never know what the last person did. I know that doesn't help but at least you know where to go with it from here
     
  10. pmrphil

    pmrphil In Overdrive GOLD MEMBER

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    If indeed the cam was not broken in correctly (or at all) the amount of garbage in the engine makes it necessary to do a complete rebuild, not just the top end. When a cam lobe gets torn up the hot metal getting sheared off the cam gets "sprayed" all over the inside, usually sticking to the piston skirts, scratching the bores, and getting trapped under/in the rings. Most times the pistons can be cleaned and reused if that's what happened. Seeing you have oil pressure problems, yank it out and rebuild - less aggravation in the long run. Just think, maybe you'll drive it more if there are no more problems.
     
    cbolt likes this.
  11. Pookieja

    Pookieja In Second Gear

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    Indiana
    cbolt, your guess is as good as mine. I think a rookie at buying on the big seen and not wanting to lose her, i had stars in my eyes and she sounded so good and all fresh looking build under the hood. probably a rookie mistake.(don't tell my wife).you know(I told u so). Even came with all the work/receipts from the building shop with everything that was done. I suppose that was my piece of mind . I'll probably start by dropping the oil pan and checking the Babbitts and pulling the manifold to check top end but ultimately i'm sure i'll just pull the engine and freshen up the e/bay and tear her down over the winter. I'll do most of the build except the major stuff if needed(fingers crossed) One of the machine shops want just the block to work and the other shop wants the entire engine to build from bottom up.
     
  12. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    If you don't mind my curiosity, what are each of them charging for their labors?
     
  13. cbolt

    cbolt In Fourth Gear SILVER MEMBER

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    Pookieja I guess you have to ask whether or not you want to spend more and have the one shop do the whole thing and get a warrantee, or go with getting the block done and doing everything yourself, and ultimately save some money.

    Your documentation proves not all rebuild shops are created equal, now are they?

    Like I said, if you lived close I would be right there helping ya. I love building motors, especially ones that are clean to begin with.
     
  14. Pookieja

    Pookieja In Second Gear

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    handy_andy I'm not sure yet. The local shop(17 miles away) asked me to tear it down and try to find out the cause and he'll do all the machining work and then i button it back up. We have not discussed cost yet he's been in biss for 30+ years. As a matter of fact he just closed down a auto parts store where the machine shop was located and now has his shop at a new location. So maybe a good candidate for experience. The other shop 45 minutes away has been there 35+ years is owned by a friends dad but he only does complete rebuilds i mean everything weather it needs it or not. I was given an about price of $5,000.+ give or take. cbolt I appreciate the offers of help man I'll probably have another friend help this winter, he was a machinist for many years and tells me we got this man just let me know when you want to do it..just the thought of it is daunting. just finished up a starter today on the F-150 that just said click--- $208. bucks later i'm tired..later.
     
  15. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    When I rebuilt the 351W for Babe, I paid a total of $700, $600 for the longblock rebuild, and $100 for a pair of freshly-rebuilt van 351 heads. I certainly saved a bunch of cash doing the assembly myself, but that 600 got me a baked & shot-peened block with machining (including line honing and torque plate cylinder honing), all the cleaning, straightening (one was bent slightly) and shot-peening of the rods and all the new pistons hung, plus the cam bearings installed. It came with the master kit, so that made me happy. I think you should get the shortblock at least pulled and torn down for inspection, just to make sure there are no bad surprises, knock on wood.
     
  16. burninbush

    burninbush In Maximum Overdrive

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    I will give you some bad news ... I had a similar problem to yours; decent pressure when cold but it quickly went down to 5psi when hot.

    A pull of the pan and a couple rod caps told the story, bearings were shot. Probably due to the low oil pressure. You'll have to have the crank ground and put in new smaller inserts. Be sure to put in a new oil pump on the way back together.

    If it has good cylinder pressure this would be a lot cheaper and much faster than a new rebuild. You'll have to pull the trans to get the crank out, but a day's work will have you back with good crank pressure. Or you can pull the block (leaving the trans in place) -- it's an easy fix with the block out.
     
  17. 6delta

    6delta In Third Gear

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    Location:
    Citrus Heights, CA
    From your initial posts I doubt if the cam is your problem. A bad cam will not run very well so you would have noticed that before the low oil pressure issue. I would drop the pan to check the bottom end but still plan on pulling it out to have it hot tanked to clean the block. With metal in the pan at least one main or rod will probably be bad. Probably a main because I think you would have probably already hammered a rod and would hear it. Although you may want to check for play in the distributor because its gear may not be meshing with the camshaft properly which can also result in oil pressure fluctuations like you described and metal shavings (That could also either be a cause of your oil pressure drop or a result of it.) Before I had a camshaft bearing tool set I would have a shop hot tank, bore if necessary (usually to match pistons/rings they were also providing) and install cam bearings. Then I would do the rest myself. Depending on what you see with the pan off you may able to decide your path better. Sometimes the crank isn't worth saving, especially since it has been gone though at least once that you know of. In addition to the crank being already ground it may also be already bored out more that you can continue to use. Being a Ford, numbers really don't matter so you may want to replace the whole shebang and just swap out your old motor for another one. (That is why I have so many engine stands.) It sucks to know the motor was rebuilt but not really know what was done and how well it was done.

    You don't reall need a lift to drop the pan --but it does make it easier
     
  18. Pookieja

    Pookieja In Second Gear

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    Location:
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    handy_andy, when i get back from Alabama next week i plan on starting the tear down.. if all goes well with finishing the wildcat. I've stalled out on the ranchero work with getting the F-150 ready for a long trip, yesterday the starter went out as i was trying to leave for a tire rotation. so a new starter yesterday, today tire rotation at Firestone..once home, new rear rotors one caliper and new pads, and oil change. my wallets getting dry and my ass is still sore from laying on gravel driveway installing starter yesterday..:confused: burninbush, I will drop the pan once on the lift just to make it easier on the back and bum, but I plan on pulling the motor after inspecting main, rod caps and snooping around...6delta, thanks for the advice i will check the distributor to be sure the gears to camshaft are not the issue. I was wondering if all the oil galley plugs were installed especially at the distributor shaft/timing cover area, this would cause low pressure.. or would that be low pressure all the time hmm. also i'll take a pic of the work order that was done and post it. it do'es show the block was bore and honed (0.20) engine rebuild 67.jpg
     
  19. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    If you knew that the engine was virgin when this work was done, you'd know instantly there would be some machining room to possibly and hopefully correct any problem. But without that info, you'd have to do a teardown and measure everything. So, pulling the pan will tell you if there is any real damage or not, and hopefully it's minimal or undamaged.
     
  20. ribald1

    ribald1 In Maximum Overdrive PLATINUM MEMBER

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    A rebuild without a new oil pump?
     

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