Top Dead Center -Distributor

1995 Blazer, 4.3 vortec vin "W". Well I took the plunge and changed the lower intake manifold gasket. Everything went back well, but I lost it on the distributor re-install. At any rate, I went top dead center on the compression stroke and reinstalled the distributor. (distributor is the tower, not the flat) Took some wiggling but it dropped in. The Blazer started, but the motor is racing up and down at idle. It runs fine with acceleration and rpm's but idle isn't right. I think the distributor is still off.

Let me see if I have this straight on the harmonic balancer. There are two slots and a paint mark on the balancer? Or is the blob of paint I'm lining the balancer up just a random blob? The paint mark should like up with the pointer on the water pump housing? I looked at the tdc line-up procedure pointed out here in another post, but he speaks of getting under the vehicle and lining the slots up with tabs. I have a skid plate under my front end and can't see the balancer from under the vehicle.

I'm also having trouble getting the oil pump to line up on the distributor. So If I get the paint mark lined up (assuming the paint mark is right) TDC and rotor turned toward #1, do I jog the crankshaft with the wrench until it fully seats or try to move the oil pump shaft with a long screw driver from inside the distributor opening? Basically, I've tried everything but cant get the distributor leg to drop, lineup and still be pointed to #1 at TDC.

Any suggestions? Anyone?

Thanks in advance.

Kevin

First do not start the engine untill the dist is all of the way down.
It has to be all of the way down to catch the oil pump.

If you are having problem getting it down the last 1/4 in.

Just hold down on edge of dist and crank engine with starter and it should drop on down.

After it drops all of the way down recheck TDC compression mark and for rotor poining to no 1 plug wire.

Then after engine start up set base timing with a timing light with bypass wire unpluged.

Thanks MT-2500. I haven't tried to start without the dist. completely seated. I tried it again this morning and just could not quite get it. I'm not giving up, just taking a break.

I do have a question about the timing marks on the balancer. I have two grooves on the balancer at about 12 and 3 o'clock, seperated by a paint mark between the two grooves at about 1 o'clock. Should I line the paint mark up with the "0"? The 3 o'clock groove? The 12 o'clock groove? I have tried the paint mark a few times, dist wouldn't drop. Tried the 12 o'clock groove earlier this morning and the distributor lined up and dropped, but obviously that isn't it because it wouldn't crank.

Lining up with the paint mark, I can rotate the dist shaft and rotor a few degrees to the left and get it to drop. Could I rotate the housing where the the cap sits a few degrees left as well (it will rotate) and line up with #1 on the cap?

One last question, does a single full rotation of the balancer change the stroke? One rotation intake stroke next full rotation, compression stroke?

Thanks again

Kevin

For tdc compression feel the piston at tdc compression.
Then use the mark that lines up with piston TDC.

The crank pulley should have a grove in it not paint marks for tdc to timing mark.

One full turn of crank puts engine on exhaust stroke.

Ok, before I read the last post, I lined the paint mark up with the indicator per the post by drdd in his post on how to find TDC after distributor has been removed. I lined the paint mark up with the indicator on the compression stroke. (picture #1 below, actually this pic is the one drdd posted with his "how to") That will be pic #1 below. drdd also posted the other two pics of the slots or grooves on the balancer. As I said, I have two grooves and one paint mark. Each of the grooves and the paint mark will line up on the compression stroke as I turn the crank. I still don't know which of the three marks I should line up with the indicator shown in the first picture. drdd shows the paint mark lined up with the indicator. Anyway, I did get the dist. to drop straight in on the compression stroke and the indicator lined up with the paint mark. The vehicle still wanted to idle with a lope. I drove the car down road and it missed at low rpms and with a noticable spark knock. So any idea which of the slots I should line it up with?

http://i465.photobucket.com/albums/rr18/flogginfaders/mark33.jpg

Here are the slots in the balancer. Slot or groove 12 oclock and 3 oclock with paint mark in between at about 1 oclock.

http://i465.photobucket.com/albums/rr18/flogginfaders/mark1.jpg

So ultimately the question is, which of the three marks should line up with the "0" on the indicator on water pump?

So ultimately the question is, which of the three marks should line up with the "0" on the indicator on water pump?

You need to set the timing with a timing light and with EST bypass timing wire disconnected
Forget the paint mark.
Use the grove that lines up when the piston is at TDC.
You can feel the piston TDC threw plug hole while turning crank by hand.
Stick a brass welding rod in the hole and feel the piston move up or down.
TDC will be when the piston is all the way up.

If it starts and runs disconnect spark bypsass wire and set the timing with timing light with the grove/mark that comes out the closeset to the timing mark pointer.
Let us know how it goes.
Good Luck

Thanks again, MT. I did as you advised and reset TDC. Turns out that the groove that is at the 12 oclock position was the ticket. The distributor dropped in after a bit of wiggling. Here's where I am now. It a bit harder to start than it used to be, not terrible, just doesn't fire up on the first turn. The idle is a bit rough, a little vibration in the steering wheel, but once you give it gas, the idle smooths out. When driving at speed it seems to run pretty smooth. Idling at signal lights etc is fairly smooth once it's been run. I ran into a store, came out, started fine and idled fine. Back at home after sitting for about half hour, it started and idled rough, but smoothed out when I gave it gas and again at speed and idled decently once warmed up. I suppose the timing is still a bit off but I feel like the distributor is at the proper position.

What do you think happens here? Is the rough idle when cold that turns into
a decent idle once its reved due to the computer catching up and correcting the idle? As I said, the timing may not be perfect but I don't have a light. I can take it to a local garage in the next couple of days and get it set I suppose.

At any rate, I feel I'm in the ballpark now and hopefully can get the Blazer purring again.

Side note: Not losing any coolant so I suppose the intake gasket replacement was a success!

Thanks MT

Kevin

You need to get a timing light on it to set the timing.
And remember the base time procedure.
Let us know what it does after putting a timing light on it.
Good luck.

Sorry for only now giving the final update. I let the blazer sit overnight and started it the next morning to test it out. It purred like a kitten. Well maybe it didn't exactly purr, but it idled very smoothly. So I suppose the final adjustment to the distributor did the trick. I still don't understand why it idled fine the next morning after not idling so well the day before. I had unhooked the battery again the day before hoping the computer would reset. After reconnecting, the idle still wasn't satisfactory.

So now I've driven it for a week and no problems. I still probably need to get a timing light on it to fine tune. But that being said, it is idling as well now as it did before I removed the distributor to do the intake job.

Thanks again for the help, MT. Next job......replace the heater core.....maybe. I had the symptoms of a clogged core (heat...but slow to heat) but no leaking in the passenger side floorboard. I used a garden hose on the heater core and found water in the floorboard after. I'm hoping that for some reason I just blew some water by the heater hose connection at the firewall when I did the flush. I'll know within a day or two if that's what I did. If not... I suppose it's a core replacement.

Yes you need to get a timing light on it to get it set right.

On the heater core see if you can back flush it with the garden hose or get water to flow threw it good.
And try reversing the heater hoses for a while.
Let us know how it goes.
Good Luck

I was able to get water to flow thru the core yesterday. Even though water was flowing through immediately, I believe I had a small plug come out. I used the garden hose with a plastic fitting clamped to the old heater hose (I had replace the old hoses with new ones on the intake job) I pushed the hose up on the heater core connectors at the firewall. I flushed in both directions. My concern was the water in the passenger floorboard I found after flushing. My first reaction was that maybe I blew the core. Earlier today, I started the vehicle and the heater on full blast. There doesn't seem to be any water leaking inside the passenger compartment. So my earlier assumption that maybe I just blew water past the fitting at the firewall and past the core into the passenger compartment seems to be the case. That's a relief because I wasn't looking forward to replacing the heater core at this time.

I'm blowing heat well at all positions including defrost. Of course it's going to have to get cold before I can tell just how well the heater is working.

I was able to get water to flow thru the core yesterday. Even though water was flowing through immediately, I believe I had a small plug come out. I used the garden hose with a plastic fitting clamped to the old heater hose (I had replace the old hoses with new ones on the intake job) I pushed the hose up on the heater core connectors at the firewall. I flushed in both directions. My concern was the water in the passenger floorboard I found after flushing. My first reaction was that maybe I blew the core. Earlier today, I started the vehicle and the heater on full blast. There doesn't seem to be any water leaking inside the passenger compartment. So my earlier assumption that maybe I just blew water past the fitting at the firewall and past the core into the passenger compartment seems to be the case. That's a relief because I wasn't looking forward to replacing the heater core at this time.

I'm blowing heat well at all positions including defrost. Of course it's going to have to get cold before I can tell just how well the heater is working.

I have had good luck reversing the heater hoses for a week to help clean heater core.

Good Luck