sportydon

i got a new truck and i am so happy , well new to me !. it is a 1990 d250 auto with less than 88,000 miles on it and it runs super. i am new to diesels but not to mechanics as i am a past certified ase master mech ( ret now lol ).
i have read most of the posts on here about 1st gen trucks and have gained a wealth of info , i plan to make some mods but not too many that i overwhelmm the 727 trans . gonna go with a bhaf (wix 42790 ) and some exaust mods and turn up the pump slightly.
i have two unanswered questions ( make that three )

1. my cruise will not hold anything over 60 mph and i want to set it at 70 , i have checked the vacuum ( 20 ) and have negligible play in the cruise actuation cable .......any advice ?

2. my throttle is very hard to hold down ( like it has a gorilla spring ) ....... is there any help for this or is my idea to lengthen the lever arm in the cab my only hope ?

3 . do ya think the throttle stiffness is affecting the cruise ?

don

edwinsmith

20 inches of vacuum seems like it should be plenty. The throttle stiffness is definately a problem though. Mine is very easy to operate. Is it stiff like spring tension or is it binding in the cable? I think the only spring necessary is the one on the VE pump. If you have an additional spring it could be the culpret. I don't have cruise on mine but On other vehicles the spring tension is definately a factor. There is probably a spring in the cruise servo also.

Edwin

sportydon

it is stiff like a spring , i can find no binding at all in the cable or linkage . there is a spring on the ve pump and the is another spring incorporated into the bellcrank assy where the throttle cable hooks on , i disabled this spring . i am kinda thinking that the resistance of pushing the transmission throttle has something to do with the overall stiffness.
IDEAS MAKE SOLUTIONS keep em coming.
don

edwinsmith

Is it significantly easier if you temporarily disconnect the tranny cable? That one should be very easy to push/pull also. There are no other springs hideing somewhere?

Edwin

boiler-rat

My throttle is just stiff enough to make me really appreciate the cruise control on a long drive. My cruise control was acting up, like dropping out when I hit a rough spot in the road. It would also drop out of over drive. I adjusted my TPS from tips I got on DTR and haven't had a problem since. I am not sure if your 90 even has a TPS but it is easy to check out if you have a digital volt meter.

sportydon

i have not tried disconnecting the trans cable , i will do that tomorrow and see if my cruise works as it is supposed to.

the 1990 does not have a tps .

thanks all

Leonard Strom

sportydon

You might try Technical Service Bulletin #14-02-90, It deals with what they call high pedal effort. I'll try to attach a link.

Leonard

http://dodgeram.info/tsb/1990/14-02-90.htm

Leonard Strom

sportydon

You might try Technical Service Bulletin #14-02-90, It deals with what they call high pedal effort. I'll try to attach a link.

Leonard

http://dodgeram.info/tsb/1990/14-02-90.htm

sportydon

AHA !!!!!!!!! now there is the answer , my trans cable has a spring built into it and the one at that link for the tsb does not . i have the right bracket as i have factory cruise , but i have the wrong trans cable and trans lever and the wrong throttle return springs.
i can do a no cost hack on it ......... remove the spring from the trans cable and re-engineer a spring to return it that has less force .
i hate to buy parts lol

rebal

thats what I did 3 days after i drove the truck off the lot
cut out the spring in the trans cable and used a lighter one I adapted . doesn't seem to have hurt it at all and it was new when i bought the truck... 250K on odometer now

sportydon

thanks to leonard and the tsb i now have a truck that is more pleasurable to drive and the cruise works as it should .
the built in spring on the trans kick down cable was the culprit in the cruise and the hard throttle .
i love it when a plan comes together and maybe i will have some contributions in the future. i can help if you have a harley sportster and need it to make power ( mine makes 100hp from 1200 cc,s ).

Leonard Strom

Don
It's to bad the original owner didn't have the throttle repaired at a dealer while it was still under warranty, it looks like it would have been covered. I've only had my smoker for a couple of weeks, with all the rain we've had I can't do any work (tweeking) on it until it drys out.
Leonard