| Author |
Message |
dounan.morton (65.96.80.66)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, September 06, 2002 - 9:33 pm: | |
can any one tell me if I should not change from a 2 valve to a late model 4 valve head.
the 4 v is coming with a jake setup. i plan on taking all related parts. this is from a turbo engine.
thanks for any input.
Do |
Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, September 07, 2002 - 5:23 pm: | |
I think your 4-valve turbo head with all the stuff would be fine. Do NOT know if the turbo mill Jake Brake had different feeler gage adjustment settings than a non turbo Jake.
You may also may have to change your timing from "S" to "A" and increase the injector size up to N65. Changing the injectors are easy-----changing the timing? I do not know, never done it.
You also may have the old style pre "N" type low compression pistons. If soooss these can either be left alone or changed out too. You would need to find out what you have inside your present mill. Good luck. |
dounanpm (65.96.80.66)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, September 07, 2002 - 7:06 pm: | |
i had been running n65
the new head has n75's i believe
i'm not sure where the timing is now, or what is in for pistons
thanks for the input
Dounan |
Tom Caffrey (Pvcces) (64.114.233.143)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, September 07, 2002 - 10:15 pm: | |
Dounan, in some of the applications that used DD engines, there was a data or configuration plate attached right to the valve cover. IIRC, it had maybe eight lines of numbers on it.
If your engine has one of those plates, then the DD people should be able to tell you exactly how your engine was outfitted.
I don't know if that was done on busses; I just mentioned it because if you should have one, then finding out what you have should be dead easy.
FWIW
Tom Caffrey PD4106-2576 |
Jim Wilke (205.188.209.11)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 08, 2002 - 9:35 am: | |
Dounan, you didn't say what bus you have but a straight 6-71 would likely mean you have a GM 4104. The engines in those buses were originally set up with standard timing, not A timing, for fuel economy. (Greyhound and Trailways didn't care how long it took for the bus to get to 65MPH, but cared very much how much fuel their entire fleet used.)
Changing the timing to A timing means removing the transmission, flywheel, all of the accessories mounted to the gear housing and rear gear housing itself to access the gears that turn the camshafts. You then move the crank and idler gear mesh 1 tooth. The gears are marked.
Obviously this project is best done if & when you need to change the clutch or rear engine oil seal anyway.
If you run the standard timing, the N65s are as big as you should go. If you change the timing you may need to use N70s. Bigger injectors will cause smoke at all speeds & use more fuel but no better performance because the extra fuel is just wasted.
Our 4104 runs N65s at standard timing and only puffs a little grey starting from a dead start. It runs clean after that. Max speed of about 75 MPH (we don't stay there long) and 9.75 MPG at 65 MPH. Not bad for a low tech machine that weighs 24,500 lbs!
Jim-Bob
4104-4039 ('59) |
dounan.morton (65.96.80.66)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 08, 2002 - 7:08 pm: | |
Jim-Bob
yes its is a 4104 -204
what happened was i snapped off all the fly wheel bolts! to make a long story short the "good" takeout motor i bought to replace it is in reality nothing more than a core motor.
so i'm going to replace the crank in my motor and change the head at the same time. if changing the timing at this time and going to N70 now will get me more power i'd like to do it
however if all it gets me is more smoke and less mileage ,than i guess its sortof a no brainer
i guess what i'm looking for is the mythicalmore power less work out of the engine. this o4 was running 68mph flatout ,i liked the speed but it was to much work on the engine i guess.
any other input is appreciated.
dounan |
Johnny (63.159.194.73)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 08, 2002 - 7:11 pm: | |
Why not just remove the snapped bolts & use your existing engine? |
dounan.morton (65.96.80.66)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, September 08, 2002 - 10:21 pm: | |
they snapped off way in , but hammered the h ll out of the holes before dissapearing. the pins were all that kept the fly wheel from falling completely away. so its remove the crank anyways.
dounan |
Johnny (67.241.166.76)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 09, 2002 - 3:27 am: | |
Drill & tap? May work, may not, but beats the you-know-what out of a crank swap. |
dounan.morton (65.96.80.66)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, September 09, 2002 - 4:29 pm: | |
has anyone out there repaired a detriot crank like that ------ lets hear .
dounan |
Dwight (67.213.8.90)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, September 12, 2002 - 6:31 am: | |
Hi Dounan
my understanding is, if the flywheel bolts broke something could be out of balance, the front balancer, if you have one, most likely needs to be replaced....to check it, mike the thickness at 4 points (12 oclock, 6 oclock, 3 oclock, 9 oclock) they should be within .010 of each other.... |
dounan.morton (65.96.80.66)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, September 12, 2002 - 6:29 pm: | |
thank you i'll be checking that
dounan |