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Top list of rookie engine building mistakes

Discussion in 'The Hokey Ass Message Board' started by Butch Clay, Oct 6, 2013.

  1. Bandit Billy
    Joined: Sep 16, 2014
    Posts: 5,795

    Bandit Billy
    ALLIANCE MEMBER

    My rookie error contribution was not the result of a lack of mechanical knowledge but more a lack of common sense.

    A long time ago, in a garage far, far way. I was helping a buddy wrench on his quarter miler when I spotted his cam shaft and Rhodes lifters for the 427 laying on the bench. A half case of Henry's later they were resting under the hood of my SS 396 Chevelle. Sounded ri-di-cu-lous, shook the antenna literally off the fender, no vacuum for the brakes, faster than hell on a Vegas Saturday night, thrilling drive...all 15 minutes of it. About the only thing salvageable where the heads, couple of rods and that cam shaft...now in a convenient three piece configuration for easier storage. I remember jumping out of the car and pulling what was left of the dipstick to see if there was moisture in the case. The antifreeze shot past my face like a pretty green water fountain in front of Caesar's. It was surprising that there was that much oil left in the block to press that antifreeze out considering the growing puddle of Valvoline on the ground that rivaled only the Exxon Valdez spill.

    It will never cease to amaze me how so many performance cars are for sale today with numbers matching blocks, evidently my friends and I never owned any of them.
     
  2. cfmvw
    Joined: Aug 24, 2015
    Posts: 261

    cfmvw
    Member

    I used to work with a guy who had a bad temper, a short fuse, and no patience. Decided to rebuild the SBC in his Suburban (which wasn't worth fixing, but that's another story...). Rebuilt it, put it back in, and a couple days later was mad at the world and the truck (which now sported his footprint in the now-caved-in drivers door) because the cam went flat and developed a knock from somewhere within. In discussing it with another co-worker, I wondered how many times he had put the motor together during the rebuild. We were both thinking the same thing, and later confirmed our suspicion: once. The last time I built a motor, I must've reassembled it several times as I checked and double-checked everything as I went along; I couldn't imagine just throwing together some expensive parts just once!
     
  3. woodbutcher
    Joined: Apr 25, 2012
    Posts: 3,165

    woodbutcher
    Member

    :D Failure to keep things as clean as humanly possible.
    Good luck.Have fun.Be safe.
    Leo
     
  4. nwbhotrod
    Joined: Oct 13, 2009
    Posts: 1,245

    nwbhotrod
    Member
    from wash state

    What clip
     
    Bandit Billy likes this.
  5. This one. I left the one out on my Cadillac 365 years ago and it came back to haunt me last year.
    retainer.jpg
     
  6. Order ZDDP additive off E-Bay...I have it shipped to NZ with no problems :cool:
     
  7. shivasdad
    Joined: May 27, 2007
    Posts: 527

    shivasdad
    ALLIANCE MEMBER
    from Texas

    Okay, I will fess up. Been super careful putting my Ford 300 back together and today was break in the cam day. I just read this thread yesterday and was mentally checking things off. So I got everything ready and what did I manage to do? Mix up the fling flang firing order! Took me thirty minutes of checking everything one more time plus a couple of nice backfires through the carb to figure it out. After I got it right (153624 damn it!) it kicked right off and went through the cam break in period without a hitch. I have usually written my notes down and I got cocky this time. Now just to get it back in the truck!
     
  8. The way I was taught to remember an I 6 Firing order back in 64 was 15 is too young, 36 too old, 24 just right.
     
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  9. shivasdad
    Joined: May 27, 2007
    Posts: 527

    shivasdad
    ALLIANCE MEMBER
    from Texas

    That's what threw me. I'm old enough now that I transposed 36 and 24. I'd rather have a 36 anytime over a 24 nowadays. :rolleyes:
     
    shawnsauto1 likes this.
  10. I know, things change, but I still refer back to that formula now and then. The one that always throws me are 4 cylinder engines.
     
  11. c-10 simplex
    Joined: Aug 24, 2009
    Posts: 1,331

    c-10 simplex
    Member

    Could you, or anyone else (yes i know the thread is 2 yrs old.......) elaborate more on this; i want to set timing and carb tuning on the test stand then run it at 2000rpm plus for 20 mins, and have never heard that you have to put a load on a never run engine?
     
  12. Mike51Merc
    Joined: Dec 5, 2008
    Posts: 3,804

    Mike51Merc
    Member

    The 2000 rpm thing is for the cam & lifters to break in. The load is for the piston rings. Cam break-in comes first while standing still and needs to be done immediately and correctly. Piston rings are broken in while driving.

    Putting a load on causes the piston rings to expand resulting in greater friction which then results in the rings and cylinder walls wearing in. The problem is that friction equals heat, so you don't want to over do it.

    There are different techniques recommended for piston ring break in, but generally you want to have short bursts of heavy acceleration (creates heat) followed by gentle cruising (cool down).
     
  13. oj
    Joined: Jul 27, 2008
    Posts: 6,198

    oj
    Member

    My best advice is to never start the engine for the 1st time at night. The reason is that you have worked all day assembling, you're tired and wore out. You'll look things over and think 'Hot Damn, I can fire this bitch up!' Wait until the next morning, put your tools away, clean the work area, organize things, clean and wipe up the spilled antifreeze. Account for all your sockets, account for all the shop rags - some people actually have left them in the lifter valley when installing an intake - mentally go thru all the steps you took yesterday, spot check the bolts etc and when you are certain you've covered the bases the light it off.
    I knew a couple good ol'boys that just had to have a blower on their small block, they'd bother me for this doodad and that to cobble this mess together, they'd ask questions and argue the answers until they got quiet about it. I had to ask how it was coming along and they kicked some dirt around until I got the story on how they'd gotten everything together and said fukit, light'er off! Well, they started it up and it actually sat there runnin and ol'Harry reached over the whack the throttle of the 4bbl carbs sittin on top of the blower - he gave it a manly tug and that blower took over as the carbs were vacuum secondaries that they left the vacuum pots off tryin to figure out what spings they needed. That blower just sucked them open and it went to wide open throttle! 'Holy Shit Vernon! Shut it off, but Vernon was in a hurry and never connected the ground wire to the magneto and neither off the two dared to touch that magneto when it was workin! They admitted they could see the pistons going up and down the heads had lifted so far off the block just before a connecting rod came out the side of the engine, piston & rod just layin there steam hot. They said it was so quiet you could hear the oil gurgling out onto the ground. So, never start an engine at night.
     
  14. falcongeorge
    Joined: Aug 26, 2010
    Posts: 18,341

    falcongeorge
    Member
    from BC

    Great advice, if you have the self discipline to follow it. I have put motors in and fired them up outdoors in driving snow storms got frost bite on my feet just because I wanted to light it off, so its safe to say I dont fall into that category!:oops::D
     
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  15. c-10 simplex
    Joined: Aug 24, 2009
    Posts: 1,331

    c-10 simplex
    Member


    So is it OK to break in the cam/lifters on the stand at 2000rpm for 20 mins or so.........and THEN do the engine load thing in the car?

    Again, i've never really heard of the engine load thing.

    Also, is it ok to use synthetic oil for break in if i'm running flat lifters?
     
  16. I started my last one (last month) the same day we hooked it all up. But we put everything away and cleaned up first. Made an Ace Hardware run for some hose and a fitting for the VP gas jug, had lunch at a pizza joint. Got gas on the way back, got home and rolled the car outside. It was a bit cold, maybe 45 but we didn't feel the cold. Fired right up and we followed the Lunati recipe for cam break in.
     
  17. rgdavid
    Joined: Feb 3, 2014
    Posts: 354

    rgdavid
    Member

    In a 1979 sbc 305,
    Been as im stupid, what stops the camshaft going backwards or forwards ?
     
  18. Memphis235
    Joined: Mar 27, 2008
    Posts: 31

    Memphis235

    Didn't clean the piston ring grooves, smoked worse than before the rebuild. The oak tree limb in the backyard got a nice workout that summer.
     
  19. Mike51Merc
    Joined: Dec 5, 2008
    Posts: 3,804

    Mike51Merc
    Member

    Yes, because that's the only way to do it. Breaking in the rings requires driving the car and sometimes it takes a lot of miles. I had a brand new OT car that consumed oil for the first 10,000 miles and then not a drop for the next 100,000 miles.

    NO, I wouldn't use synthetic oil for break in. Firstly it has no zinc which is needed for flat tappet cams and secondly it's too slick for proper break in of the rings.
     
  20. noddaz
    Joined: Sep 9, 2014
    Posts: 12

    noddaz

    I did a classic on my own engine for my Camaro.
    Please make sure that the oil pick up tube is firmly attached to the oil pump. Seriously.
     
  21. treb11
    Joined: Jan 21, 2006
    Posts: 3,301

    treb11
    ALLIANCE MEMBER

    The distributor.
     
  22. Gene Boul
    Joined: Feb 9, 2006
    Posts: 807

    Gene Boul

    It's always good to have "4 eyes". Don't be too embarrassed or too proud to ask someone else to look it over. I've been doing it for over 40 years and still like someone else's input! Again...if it doesn't look right it isn't! I turn the engine over 360 after almost every event! Torque should increase proportionally.
     
  23. When installing a bolt, nut or machine screw (with standard right hand threads) turn it counter clockwise (don't panic, there is more to the sentence), when it drops into the thread turn it clockwise to tightened it.

    Charlie Stephens
     
  24. av8
    Joined: Mar 3, 2001
    Posts: 1,716

    av8
    Member

    Excellent advice for one of the more common problem areas on SBCs. I learned a similar scheme from a sprint-car engine builder years ago; clean the end rails of the block with lacquer thinner, coat the bottom of the cork gaskets with weatherstrip cement (similar to Gaskacinch), set the gaskets in place while still wet then pull them off and let both the gaskets and the block dry before putting them back in place. This results in a co-hesive bond that holds the gaskets firmly in position. Finish off with a tiny--repeat tiny--daub of silicone at the end of each gasket, and line up the manifold over the block and set it straight down and into position. Hundreds of leak-free passes on a drag motor, and each time the manifold was removed the gaskets remained in place.
     
  25. av8
    Joined: Mar 3, 2001
    Posts: 1,716

    av8
    Member

    Don't beat yourself up about that; countless Honda twin and single heads had their cam journals worn out by thoughtless owners who ran them with dirty oil. BTW, many of those wonderful heads can be saved by being converted to needle bearings; not cheap but well worth the dollars for keeping some of those little killers running.
     
  26. elba
    Joined: Feb 9, 2013
    Posts: 611

    elba
    Member

    1. The first Chevy engine I ever O/H ( 16 years old ) I only torqued the heads one time - that didn't turn out good.

    2. Don't put stock 1.94 heads on a stock 283 - compression ends up about 6:1 NO POWER !

    3. Keep a fire extinguisher in your car - bad feeling when carb backfires and catches fire because I didn't put the air cleaner on ! Got it out but heart was racing.
     
  27. falcongeorge
    Joined: Aug 26, 2010
    Posts: 18,341

    falcongeorge
    Member
    from BC

    not really, its actually the taper on the lobes. If you doubt this, try putting a roller in it with no thrust button, you will find out.;)
    This is also why running a lot of valve spring will make the cam gear chew up the block face if you dont run a thrust washer behind it.
     
  28. av8
    Joined: Mar 3, 2001
    Posts: 1,716

    av8
    Member

    The task of correctly cleaning threads on an engine being rebuilt is more important than I thought about years ago, back in my OHV days, when I merrily ran taps down all threaded holes I could reach, thinking I was doing my engine a favor by being very thorough. It wasn't until I got reinvolved with Ford flathead V8s better than a couple of decades ago that I learned that I had probably done as much harm as good in many cases with the indiscriminate application of thread-cutting taps where another tool would have been more appropriate and less damaging.

    The goal is to clean threaded holes and restore them to their original condition. This is not what you want to do with thread-cutting taps. I include one of the better explanations of the situation that I've read.
    A thread-cutting tap is designed to cut threads. It will never engage the already cut threads in the same manner every time. You can take a new drilled and tapped hole and run the tap back through it and it will remove more metal. It won’t only remove material from one side; it will remove it from the entire circumference of the hole. It is almost impossible (by hand) to get the tap lined up in the exact same orientation to retap a hole.

    In a poor example that I can do like this the first time you cut the threads they will look like this > <, every subsequent time you run a thread cutting tap through the hole will remove the point of the threads and round them off, reducing your thread depth making them look like this ] [. This is from the tap being slightly out of alignment with the original threads and it is cutting the threads in the alignment it is at now. That is the material that is getting removed.

    What are you wanting to clean out? If its a non stressed part then using a normal tap wont be a really big deal. I would not use a normal tap for any critical fastener. Something like and intake or accessory bolt holes is no big deal. But definately use a thread chaser for something like
    main bearing caps or head bolt holes. Just bear in mind that threads cleaned with a normal tap wont be able to take the same torque load due to the reduced thread depth and contact area.....cutting tap is designed to cut threads. It will never engage the already cut threads in the same manner every time. You can take a new drilled and tapped hole and run the tap back through it and it will remove more metal. It won’t only remove material from one side; it will remove it from the entire circumference of the hole. It is almost impossible (by hand) to get the tap lined up in the exact same orientation to retap a hole.

    In a poor example that I can do like this the first time you cut the threads they will look like this > <, every subsequent time you run a thread cutting tap through the hole will remove the point of the threads and round them off, reducing your thread depth making them look like this ] [. This is from the tap being slightly out of alignment with the original threads and it is cutting the threads in the alignment it is at now. That is the material that is getting removed.

    What are you wanting to clean out? If its a non stressed part then using a normal tap wont be a really big deal. I would not use a normal tap for any critical fastener. Something like and intake or accessory bolt holes is no big deal. But definitely use a thread chaser for something like main bearing caps or head bolt holes. Just bear in mind that threads cleaned with a normal tap wont be able to take the same torque load due to the reduced thread depth and contact area.....


    Fair enough -- don't do it. Instead, use thread-cleaning "taps" like those sold by Summit and other folk -- $16.00 for a set that's likely to handle your needs for several motors. Or, you can make your own critical thread cleaners like my favorite flathead Ford V8 head bolt/stud cleaner fashioned from a decent bolt with three flutes cut into it with a cutoff wheel, a bit of tapered lead fashioned on a belt sander, and a T-handle welded to the bolt head.
    [​IMG]

    It works like gangbusters and won't hog-out and ruin threads.
    But the best advice is still -- don't clean old threads with a thread-cutting tap!
     
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  29. junkyardjeff
    Joined: Jul 23, 2005
    Posts: 7,244

    junkyardjeff
    Member

    Cleaned out the block but do not remember cleaning out the oil passages in the crank and now I have a 57 235 with less then 15,000 miles that has major scoring on the journals and toast bearings,replaced the rod bearings to get me by until the new motor is ready and did not check the mains.
     
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  30. diiulio
    Joined: Dec 1, 2006
    Posts: 47

    diiulio
    Member

    What is the right way for pistons in a flathead? I am about to finish up an 8ba that is .060 over on cylinders and .010 on the crank, stock.

    This is my first engine build and don't have anyone to look over my shoulder as some of you have mentioned. I have checked main clearances, rod clearances, piston clearance in bore, ring gaps, crank end play, valve adjustment, valve spring pressure, valve to head clearance, piston to head clearance, and I think that sums up the clearance checks I have done.
     

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