High idling problem

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High idling problem

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High idling problem - 12/9/2007 9:35:35 PM

iceman_12_18_87

Posts: 3
Joined: 12/9/2007
Status: offline

just rebuilt an 1985 305 no drag motor or anything the oil pump went out in the truck my dad left me and spun a main bearing(wish i wouldve just put a crank kit in it) but i had the heads rebuilt at a local shop and i was told they were 350 heads which i dont think is part of the problem but after re-assembling the motor o go to fire it up it cranks fine i mess around with the time a little bit but its still idling way to high since i dont have a tach in the truck i dont know exactly how high im guessing around 2500 to 3000rpm my brother thought it might be the factory 2 barrel carb so i have it rebuilt same thing then my brother tells me to buy a new carn buy a new carb to shut him up same thing now i have over 300 dollars in TWO BARRLE carbs i fire it up same old thing idles high. i remember when reasssembling my brother had me put an extra half a turn on the vlaves after adjusting them cause after turning the motor over they did you could still spin the push rods easily to. but i was just wondering if anyone could helpl me out with this its a truck me and my father fully restored before he passed and i would really like to have it back going so any help would be greatly appreciated. also tomm. im gonna go and pull the valve covers and take that extra half a turn back out of the valves ill repost if that fixed it but i doubt it will do any good

Post #: 1

RE: High idling problem - 12/14/2007 4:48:36 AM

astroDZak

Posts: 84
Joined: 9/2/2007
Status: offline

Make sure your carb is completely shut down (look downthe throat and see if butterfly is closed COMPLETELY.
Warm the engine up and try timing it after it is warm. If the engine will not time right using a carb cleaner spray around the intake, carb and anywhere else there could be a vacuum leak.
If theres a vacuum leak it will change the engine idle with the flamable spray.
Are you positive the timing marks were right on the timing gears before you put it together? If they are wrong you won't be able to make it run right when timed right if you can even get it timed.

(in reply to iceman_12_18_87)

Post #: 2

RE: High idling problem - 12/15/2007 3:45:15 PM

cplthomas

Posts: 16
Joined: 12/15/2007
Status: offline

I think you got alot of stuff going on with this mill.
Get a refund on the new carb, the old one will do (especially since you already rebuilt it) buy a chiltons or another shop manual (stay away from haynes).
You need to find the proper guage tolerance for the valves, ensure you know where TDC for #1 is and start the valve job over. You will have to buy a feeler guage, but who doesnt need more tools?
Was the dizzy removed during rebuild? if so was it put back exactly in the right spot, you could be 180 deg retarded.
The 350 heads should be fine - do a compression test just to be sure.
Like astro said, check for a vacume leak too, I like to spray starting fluid areound the base of the carb and the intake manifold seats.

(in reply to astroDZak)

Post #: 3

RE: High idling problem - 12/16/2007 11:25:05 PM

iceman_12_18_87

Posts: 3
Joined: 12/9/2007
Status: offline

ok ill check the butterflies in the carb but i did disconnect my throttle cable and pulled the ear on the carb forward to check such but i didnt think to look down the carb yeah the distributor was removed but i got number 1 at tdc then marked the distributor and the block to assure proper alignment and when adjusting the valves i did make sure the number 1 was at tdc. ive got a set of feeler guages so i guess ill pull the valve covers again and adgust them that way. the haynes manual said to get number one at tdc and spin the pushrods between your fingers until they didnt move any longer (which i thought was kinda general like) rotate the motor 90 degrees and adgust number 8 and so forth but first ill check for vacuum leaks and post back. if i cant find any vacuum leaks im gonna re-adgust the valves and if im still havin probs im gonna pull all my accessories back off the front of the motor and check the timing chain gears again thinkin im cramped on space for that though so ill probably just pull the motor again to make sure i get everything right and go from their. thanks again guys ill post back as soon as i can

(in reply to cplthomas)

Post #: 4

RE: High idling problem - 12/16/2007 11:37:25 PM

iceman_12_18_87

Posts: 3
Joined: 12/9/2007
Status: offline

dang i just remembered that the bottom of the timing chain cover seats itself on the oilpan so if i do check my timing gears im thinking i will have to pull the motor unless i can get it to slide free of the oil pan

(in reply to iceman_12_18_87)

Post #: 5

RE: High idling problem - 12/17/2007 4:12:56 AM

astroDZak

Posts: 84
Joined: 9/2/2007
Status: offline

Good luck getting the timing cover back on without dropping the oil pan anyway. It can be done and I have done it but not without cutting back the corners of the lip and extra silicon. Also a few choice words helps too.

(in reply to iceman_12_18_87)

Post #: 6

RE: High idling problem - 12/17/2007 7:51:05 AM

cplthomas

Posts: 16
Joined: 12/15/2007
Status: offline

Remember to make sure you are on the proper stroke (intake) when at TDC.
Sux to have to remove the pan too.
It doesn't have to come completely off - seems like a shame to waste a perfectly good gasket(s)

(in reply to astroDZak)

Post #: 7