What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

86 350 K5 Blazer not starting after rebuilt + white smoke through carb

P

Philouw

Registered Member
Joined
Oct 17, 2015
Posts
55
Reaction score
0
Hey everyone,

I recently replaced the camshaft on my K5, along with the timing gears and chain, the lifters, and valve springs. My plan was to leave the old valve springs for the break in (softer) and then once the break in was done, remove the heads and change the valve springs.
After putting everything back the first time, the truck started right away, and everything broke in correctly. Then I removed the heads to change the springs, and now they I've put everything back again, it won't fire up. It fires but not even for a second, and dies right away, it struggles. I've put the initial timing at 10 deg first, then 14 deg, but id didn't change anything. On top of that, there's smoke coming out of the carb everytime i start it.
Would the chain skip a tooth ?? even if it's new and the truck started correctly the first time ? is it the ignition timing ? I'm lost... need help :/

Thank you.
 
Start from the beginning and re-time it.
 
I'd re-time the distributor from scratch; position the #1 cyl, check distributor position, check plug wires, etc..

The chain is a possibility but I'd rule out the easiest stuff before cracking it open again.
 
nvrenuf said:
I'd re-time the distributor from scratch; position the #1 cyl, check distributor position, check plug wires, etc..

The chain is a possibility but I'd rule out the easiest stuff before cracking it open again.
Click to expand...

Ok I'll do that. What ignition timing do you suggest ?
Another thing, don't know if it's relevant, I just started it one more time, and a flame came out of the carb. So that would confirm an ignition problem ?
 
If you said it fired up and ran for the "break in". Then you pulled the heads to change valve springs. Ok, you must have the distributor stabbed wrong. Do what nvrenuf said, bring it up to TDC and see where your rotor is pointing, should be pointing at number one on the dizzy cap. You will get it, hang in there.
 
livid4dirt said:
If you said it fired up and ran for the "break in". Then you pulled the heads to change valve springs. Ok, you must have the distributor stabbed wrong. Do what nvrenuf said, bring it up to TDC and see where your rotor is pointing, should be pointing at number one on the dizzy cap. You will get it, hang in there.
Click to expand...

Well, I've put the distributor rotor at sparkplug wire #1 when it's 14 degrees BTDC on the balancer, should it be 0 ?? (no advance)
 
TDC will be at zero on the balancer, with number one piston on compression stroke. I think you found your problem.
 
livid4dirt said:
TDC will be at zero on the balancer, with number one piston on compression stroke. I think you found your problem.
Click to expand...

Well I hope that it will solve the problem, I'll try that and let you know.
Just one question: why do people choose to fire up the spark plug at between 10 and 16 degrees before top dead center ??
 
That all evolves around the timing specifics, once you get the dizzy set right. I am by no means full of all of those answers. I have learned by trial and error, lot's more error....lol. Someone with more knowledge can answer that for you.
 
So, I tried distributor rotor pointing at sparkplug tower one at TDC 0, and it didn't work, but I tried 16 BTDC, and the truck started, but was still dying. I then put 20 BTDC, and it was more smooth... I feel like 20 is way too much isn't it ? The cam is not stock, so I don't know if it should change anything for the ignition timing...

Would the timing chain be off, and increasing the advance that much was sort of rebalancing the whole timing ?

Thank you for your advice
 
Your probably still one or two teeth off on the distributor--pull it back out and turn the rotor one tooth towards the rotation you had to turn the distributor to get it to start--then put it back down..you may have to use a long screwdriver to align the oil pump drive tang,or have someone crank the engine while you push down on the distributor,to get the tang engaged,and let it drop in all the way--...then you can turn the distributor with it running, to time it..
Only go one tooth at a time..
 
So, i should go 21 or 22 BTDC, is that what you mean ? but isn't it too much of an advance ? Or the start up advance has nothing to do with the initial advance ?
 
Back to square to one. Don't even look at the timing mark right now, pull the number 1 spark plug, disconnect 12 volt source to dizzy.
Get a helper, if you can put your finger tight in spark plug hole, have someone bump the starter (small increments), once your here or feel your finger getting pushed by compression.....stop riht there.
Now take a look at the timing mark on balancer, line up zero with the timing pointer "LEAVE RIGHT THERE".Now you can pull the dizzy and restab, this will be necessary.
 
Yes, i did put the engine at 0 TDC on compression stroke, and it didn't start and it backfired. Then I tried to put it at 16 BTDC, and it worked better, but was still sluggy. I've put it at 20 BTDC and it was smoother :/ I don't understand...
 
I'm not even reading these answers.. but your getting way ahead of yourself with pointing rotors at #blah, blah, timing #'s, etc..

bring the motor to TDC... either by watching the #1 valves or feeling for compression.. see where the rotor is pointing.. it should be pointed at the #1 cylinder, but it doesn't have to be.. all that tells you is where to start lacing #1 on the towers.. you can restab it so it is pointed at #1, but you may have to manually turn the oil pump drive...

fire the engine up.. than time it.. most SB's are 4 to 12 depending on yr, etc.. but non stock cams, etc can call for more initial, different curves, etc.. but just start the motor at TDC and go from there....
 
You must log in or register to reply here.

Latest Posts

Top Bottom