I'm Baffled

Discussion in 'Ranchero Tech Help' started by thegasman, Jan 14, 2020.

  1. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    Man, that's gotta hurt if the rubber fails enough for the ring to pop off. I'm guessing some form of racing?
     
  2. thegasman

    thegasman In First Gear

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    Hey everybody. Finally got some good weather and time to run some checks on the engine. Took a compression test on each cylinder. Compression wasn't great but at least they were all within 10 psi of each other. Had 135 psi on a couple of cylinders and 145 psi on a couple of cylinders and 140 psi on the rest. I then hand cranked clockwise the HB to line up with the TDC timing marks to get the slack out of the timing chain. Pulled the dizzy cap and ' lo and behold ' the rotor was pointing towards the #4 plug wire on the cap. That explains the timing light reads on #4 and #7. Slowly backed up HB ( counterclockwise ) to see when the rotor in the dizzy would move. After about 20 degrees of HB movement the rotor started to turn. I think that means probably loose timing chain at the least. I will have to pull the timing cover to check out the timing set and replace parts as necessary. TWO questions for anybody : #1 - any ideas on timing chain vs timing gear besides timing gear might be louder. #2 - any ideas on compression readings being a little low or don't worry about them since they're all about the same. If they're going to be a problem, might have to take care of them while working on timing issue. Engine doesn't smoke at all right now. Thanks in advance everybody.
     
  3. Hillbilly

    Hillbilly In Maximum Overdrive

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    If you like enough noise to drown out bad bearings, convert to gears. My favorite replacement gear and chain set is a Cloyes True Roller, double row chain and gear set. Not cheap but very long lasting. Tip on longer chain life = Pour a quart of new oil in a clean pan and soak the new chain overnight before installation. The Cloyes timing chain will stretch a few degrees then stabilize so re-check your base timing after a couple hours of run time. I would venture that your low compression readings are a result of incomplete cylinder filling due to the retarded valve timing you currently are experiencing. Now, you might not like this but if you have a destroyed plastic tooth cam gear - - You really need to get those chunks of plastic out of the oil pan and oil pump pickup screen.
     
  4. 72GTVA

    72GTVA Administrator Staff Member

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    X2 ^^^
     
  5. burninbush

    burninbush In Maximum Overdrive

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    Re 72gtva and Hillbilly -- neither of you mentioned toothed drive belts? Any strong feelings about those? In truth I don't know if those are available for Ford motors.

    Within my knowledge of timed belts, they don't stretch. I had 3 Chrysler v6 motors that used a long belt; two were replaced at 80k ~120k miles, after water pump failures, third car in search of a cam sensor problem; still showing perfect timing. And I do mean zero error on the three timing marks. They used an oil-pressure gizmo to keep them at zero play.
     
  6. 72GTVA

    72GTVA Administrator Staff Member

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    I don't know that they are available for that era V8 - first encountered a timing belt in a Ford on a 4 cylinder I4 in a 1979 Fairmont Futura. My neanderthal attitudes and dinosaur brain isn't very receptive to that idea to be honest (my fault if you wish). Haven't read of them being available and haven't researched them so will defer to wiser and more open minded folks.
     
  7. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    There are toothed belt drives, but really, they're for race cars, where you are disassembling the engine after x-number of passes or x-number of minutes of racing. So the Cloyes set (I put a set in Babe's 351W) would be the set to get.
     
  8. Hillbilly

    Hillbilly In Maximum Overdrive

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    Watched too many belt failures on engines in the past to even consider the good points of cog belts. Interference engines, ones that if the belt brakes an open valve smacks a piston resulting in serious damage turned me off to the idea of belt driven cams. Belt reliability may have improved but they aren't registering in my Neanderthal brain. Still not sure about those long chains in over-head cam engines as they stretch if poor quality oil is used in the engines.
     
  9. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

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    I ran a belt drive on my 351W powered dragster (Yates external, dry) which are no longer available (other than the Danny Bee unit). Cannot be used with a normal water pump, not the piece you would ever use on a street driven vehicle. Ford (SVO) once produced a wet belt system that fit in a stock timing cover, but it wasn't available long, most likely because of lack of longevity problems. Get the Cloyes Street True Roller.
     
  10. beerbelly

    beerbelly In Maximum Overdrive SILVER MEMBER

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    Speaking of long chains- SOHC Ford Cammer!
     
  11. 5.0 Chero

    5.0 Chero Bahumbug Staff Member

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    why us no one asking why is the rotor pointing to number 4?
    with marks lined up with pointer rotor should be pointing to 1 or 6
     
  12. Hillbilly

    Hillbilly In Maximum Overdrive

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    Good question Carl. Possibly dizzy has been stabbed in that far off then the firing order was moved on the cap to make it run ? Chain jumped that far off ?
    Ever been around a Cammer Beerbelly ? Those long chains can lift the engine oil like a pump leaving no oil in the pan if you try an extended high rpm run. Fine for no longer than a drag race but not funny out on the salt flats. Takes a dry sump system with a big reservoir tank to combat oil starvation.
     
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  13. beerbelly

    beerbelly In Maximum Overdrive SILVER MEMBER

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    Ever been around a Cammer Beerbelly ?
    Never have Hillbilly, but I've seen photos. I was amazed that a high performance engine could stay accurately in time with those lengths of chain.
     
  14. 5.0 Chero

    5.0 Chero Bahumbug Staff Member

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    Dizzy being stabbed wrong would have nothing to do with timing mark lining up with #4 plug wire do not think it could run with the chain off that far cam to piston timing wise[/QUOTE]
     
  15. cbolt

    cbolt In Overdrive SILVER MEMBER

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    Back in the 70's when my 302 jumped a tooth due to nylon timing gear teeth it wouldn't run at all, so it doesn't seem likely to me it would still run after jumping a tooth. At this point I would find tdc, reset your timing, and seeing what happens when you fire it up. And by finding tdc I mean disregarding what the timing mark says and use the tried and true removing the #1 plug and rotating the engine until the pressure blows your finger off the spark plug hole trick. From everything I read in this thread I would say you have a timing gear issue and will most likely be starting with replacing the timing set, but it could also be the distributor itself as I recently had a crazy distributor problem that was somewhat similar. Good luck and keep us posted.
     
  16. pmrphil

    pmrphil In Maximum Overdrive GOLD MEMBER

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    I still think the distributor gear roll pin sheared. It 's a fairly common problem.
     
  17. Hillbilly

    Hillbilly In Maximum Overdrive

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    Very valid point pmrphil. Until a tear down and serious inspection of every component is done all we can do is speculate on the cause of this mystery. Whatever the real culprit is, it should be very obvious after a teardown is done. Guessing about the cause from past experiences we have encountered does give hints as to what to look for. At least it is likely to be nothing majorly messed up.
     
  18. TestDummy

    TestDummy In Maximum Overdrive SILVER MEMBER

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    That's why I haven't chimed in with a theory. Been waiting on the tear down.
     
  19. handy_andy_cv64

    handy_andy_cv64 In Maximum Overdrive SILVER MEMBER

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    I actually had that on my '89 Bronco 351. The gear and shaft were sufficiently worn between them to cause the force of rotation to shear the roll pin. Died on me while I was heading to a job interview, but I cranked it enough to spin it back around and get it to restart. After I got home from that debacle, I pulled the dizzy and found the problem. I had a spare dizzy, swapped in the roll pin, and a few days later it quit again.
     
  20. thegasman

    thegasman In First Gear

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    Thanks everybody for all the suggestions. After much research and thinking, I decided to pull the motor, find the problem and fix. And in doing that, I going to REFRESH the old motor while I have it out. According to my research the 400s back in the day ( 1973 ) had timing chains with built in cam retards for emissions. The cam and crank sprockets were set up so the cam would be as much as 6 degrees retarted from the factory. An after market timing set is coming for sure. Research says be sure not to over cam on these engines. You want torque down low in the powerband. A 268 degree duration cam should work fine. I think that's going in too. The stock open chamber heads flow well and it's the low compression that was the motor's problem. If I get a valve job done and have the heads milled 0.030 , that should raise the compression up a little. Adding a dual plane intake like the Edelbrock Performer should aid in the flow. And lastly, they said to make sure not to over carb. Supposedly a 600-650 cfm carb with vacuum secondaries would fit the bill. They found an old 400 engine and did these mods to it. Before the mods the engine was putting out about 100 HP. After the mods the engine was putting out 382 HP and 456 lb-ft of torque at 4,400 rpm. All for under $ 2,000 at the time the article was written ( couldn't find the date of this article ). The best thing about this article, the machine shop that did the work is only 20 min from my house. I plan on dropping by next week to see if they're still in business and if they are, do they remember working on so-call engine. If they still do that type of work, see what kind of time line would work for me. I'll pull the motor and drop it off and hopefully have it back by some time by the end of March. Don't drive the Ranchero in cold weather anyway and I never want to rush anybody when they're doing IMPORTANT work if you know what I mean. Prices probably have gone up since this article was written ( article seems kind of old - at least 5 years ) but hopefully not too much so I can afford it. If not, I'll have to do it piece meal - little bit at a time. Thanks everyone and I'll update when I find out what the original problem was.
     
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