problem it kept going slower??

Discussion in 'Race 400/430/455' started by Dubuick, May 10, 2004.

  1. Buicks4Speed

    Buicks4Speed Advanced Member

    Vaccum leak

    Your high idle is most likely from a vaccum leak. It idles high initially from the rich mixture and the extra air from the leak until the mixture leans out and the idle backs down again. I'm sure when you put it in gear it has an initial hesitation when you hit the gas with a load on the motor. If your carb gasket is good and there is no missing plugs in you intake it is most likely your intake gasket on lifter galley side since I would think you would notice it if you had a leak on top. You can try a can of carb spray/cleaner and mist it over your carb to see if your idle jumps up when you richen up the mix with the spray. Also you can spray it over the gasket area of the intake to find a vaccum leak. Either way, if the idle takes a noticeable jump you got a vaccum leak. I've seen the intake gasket slide down on installation and cause a leak on the lifter galley side and give the problems your describing. Good luck. Don't be scared of using the carb spray, you wont hurt anything. I've used it to diagnose bad fuel pumps/fuel problems on fuel injection cars. You can keep a car idling briefly on spray alone. At least enough to get it in the garage. :grin:
     
  2. carcrazy455

    carcrazy455 Well-Known Member

    Dubuick, if you checked the timing and it moved (retarded) without the distributor moving in the front cover you need to replace the distributor gear (you probably had what felt like a miss or studder on the run where it jumped a tooth or two). I have ruined more distributor gears than I care to count and I do not even run a hi volume oil pump. I have actually ruined a couple of cams by not changing the gear once I notice the timing retard.

    Since we are on this subject does anyone know of a cure?


    Mike
    carcrazy455@yahoo.com
     
  3. Buicks4Speed

    Buicks4Speed Advanced Member

    Mike
    Put a bass oil pressure gauge line inside the front cover that feeds off the pressure passage in the front cover and rap it around to spray oil on the back side of the gears were the mesh. Use the 1/8" pip fitting that comes in a gauge kit. Cut the end of the line that faces the gears with a pair of snipe the crack it back open by squeezing the sides or use a needle drill to drill a small hole @.016-.020". This should help or cure your problem. You may have an alignment problem. Have you ever used gear marking compound to check the mesh on the gears?
     
  4. Dubuick

    Dubuick CMDR Racer

    Well I got around to checking the car out more the timing was at 2 degree total advance and -12 at idle. i pulled the distributor and the gear was like a knife egde I put it back in one tooth back set the timing to 30 and it ran great the idle was nice and smooth so that was my whole problem! I ordered a new gear and i looked at the cam and it looks ok not perfect so is the metal hard on the cam than the gear?? and I have run this same set up last year with out a issue like this this year i have 18 passes on the car and the gear is toast what causes this i did have high oil presure for i while but i got it down before the last time i ran the car......On another note my oil pan gaskit at the rear is leaking like crazy all of a sudden does anyone have the 9 quart pan from t/a it fits like S#@T I wounding if anyone else as had better luck than me with it? or any tips on sealing it better now that i have to pull the motor out and change it..but everyone thanks for all the suggestions I would have been chasing this for a while before i checked the timing i figured it was in the carb..
     
  5. bgs455

    bgs455 OIF OEF HOA ONE

    Do you're self a favor and get a bronze dist. gear. Do not drive the car untill you get a new gear. I had the same problem 2 years ago. I did what you did, and went to go get some gas and as soon as I put it in gear pop, bang, engine died. That hi vol-hi press pump cost me over $400 in the end. I've been running the stock pump (properly set up) and have had no problems since.
     
  6. carcrazy455

    carcrazy455 Well-Known Member

    Dubuick, if the cam gear has a knife edge you may need to change the cam as well (I know from experience). The bronze gear is OK if you don't mind changing them often (but they will save the cam). Get the steel gear direct from MSD for $13 bucks or go bronze for $40 (but MSD does not sell bronze for Buick last I checked they said there was no need and I could not convince them otherwise). I have been replacing the distributor gear sometime between 100 and 200 runs. I think it helps gear life if you have an oil temp gauge and only rev the motor once the oil is hot (thin). If Redline Ron Rygelski ever shows up again I will try some synthetic oil.


    Rick, I had not thought of checking the tooth mesh on the gears. What is the pattern supposed to look like and how do you change it if it is off (shim the cam against the block or the distributor against the front cover)? I have tried the oil feed in the front cover and did not see any difference (it is a race only motor so it does not have much time to wear normally). I think the cam moves at hi RPMs and that causes the alignment to change and the gear to wear.

    Thanks
    Mike
    carcrazy455@yahoo.com
     
  7. Dubuick

    Dubuick CMDR Racer

    well here is a picture of the gear the picture isn't that good but you can see the damage
     

    Attached Files:

  8. Buicks4Speed

    Buicks4Speed Advanced Member

    Your gear mesh looks ok going off the wear on your gear. Sometimes I've seen there being some type of shift that cuases the gear to a little shallow and a different front cover useually fixes it. Also I've seen the pattern ride on the high side on the gear and I've put a shim between the distributor and the cover. As bad as your gear is wearing, it appears you have alot of internal pressure inside your pump. If you run a high-volume pump you have to "port" the front cover and the filter plate to accommedate the extra volume from the pump otherwise it just eats everything up. A pressure feed line off the bottom plate to the rear of the motor is a good way the get some of that extra pressure off the pump and in the motor but you have to get the oil out of the pump first. There is a thread "oil pans" under the history in this race section that has a few good pics.
    What I mean by extra pressure is you could have 120 psi in the pump and have only 70 at the motor.
     
  9. Dubuick

    Dubuick CMDR Racer

    well the only thing is that this the same front cover the same oil pump gear and kit i have run for four years now and never had a issue before but after reading the post from mike he said have a oil temp gauge to see temp when i was racing last it was in maine at a 1/8 the outside air temp friday night was 39 degrees and i don't think i had the oil temp up high engough the water temp was 170 but that doesn't mean the the oil temp was up and when i think it jump was in the burn put when the poped
     
  10. john hixon

    john hixon Well-Known Member

    Hey Mike (DuBuick),

    Just checking back to see if you've got everything sorted out and find out if you made any changes to your previous set up. I had the exact same thing happen to me in June, however I wiped out the cam gear too.

    I just got everything back together and after breaking in the cam and making a couple tuning passes my new bronze gear is beginning to knife... It's not terrible, but I'm definitly not going to get another 50 passes out of it.

    I'm running a booster plate and adjustable regulator. It also has the "white" spring (60lb). After talking with Dave at TA, I'm replacing it with a "stock" spring to see if there is any change. Evidently the higher pressure springs can bind up when running the adjustable regulator, further aggravating the problem.

    -Later.

    John
     
  11. Dubuick

    Dubuick CMDR Racer

    Well, I took the front cover off had a new cam in hand, when i look at the cam gear it look border line so I removed the hi vol kit use the stock spring spend like 3 hours working on the pump setting it up correct with a dial gauge .003 end play had to hei-coil the bolt holes running a broze gear I have 10 passes on it know and it look to be holding up it shows signs of wear but nothing bad look like it will last out the season. I'll change the cam this winter When I pull the motor I didn't want to wreck a new one i want to make sure i fixed the problem
     
  12. john hixon

    john hixon Well-Known Member

    Yeah. I may need to better check my clearances. The shaft spins pretty easily by hand before oil pressure is built, so it doesn't seem to be binding.

    Overall it's just a pain to deal with. I'm back where I started though. Knocked out a couple 10.90 somethings without much tuning. So at least I'll get some additional racing in this year (knock on wood).

    Good luck to you.

    John
     
  13. Dubuick

    Dubuick CMDR Racer

    Yea i know the feeling I'm having a tough year lot of dumb issue right know i'm tring to get a dominator to work right Well good luck!:TU:
     
  14. 72GSX

    72GSX Well-Known Member

    Hello, not to change subject or start anything, but I saw a car sit forever with a real high stall converter on the line because the guy in the other lane would not stage and was fooling around. It was a night race and people could see the converter glowing red under the car I was amazed it didn't start a fire in the trans. The guy got out and almost killed the guy in the other lane, my feeling was why are you sitting there against the converter so long, he should have backed out of the lights when the other idiot staged to return the favor, just my 2 cents. Tom
     
  15. buick535

    buick535 Well-Known Member




    Yes, this is exactly what I have talked about in the past. People do not believe how hot a converter will get sitting at stall on the starting line. I can guarantee you he wasted the fluid and has probably already damaged the trans, may not show up for a while.
    I do not understand why a guy will sit there against the converter when the other guy is not even in the lights yet. I've seen it many times. Jim Burek P.A.E. ENTERPRISES
     

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