Hey guys,

So I got the distributor, but no dice on a decent scan tool.

We decided to just wing it because it seems like it would be easy going after getting TDC...

Then we done fudged up. We took out spark plug #1 and put in a compression gauge. First mistake was that we took out the old distributor next (since the gear was loose I didn't think its position meant much). Then we quickly realized that we couldn't easily turn the crank pulley in order to check for compression (fan was in the way, kinda hard to turn, etc). Eventually realized it was better to get all the pulleys turning from turning at the alternator. We could hear air escaping, seemed to be at the hole left from where we took the distributor out. Put the old distributor back in to stop that but no noticeable compression on the gauge. Tried doing it by thumb instead but nothing noticed.

Ugh, not sure what to do now because we need that TDC. Can't just throw in a distributor because we buggered it all lol. Please, any suggestions?? Buddy was suggesting cranking the engine (without ignition system installed) to try to get compression, but I don't know about doing that.

 

Remove front skid plate and that will give you access to the crank bolt. Watch this.

 

To get tdc you could pull the spark plug and have a helper stick a screwdriver into hole to feel the piston come up

When I replaced my distributor I had trouble getting it in so I took the old one ground the gear off then you can freely turn it while inserted turn it to correct position then remove it and drop the new one right on in

 

I've seen this video about 10 times, and it has nothing about TDC (he says right in the video that he has another video on finding TDC, but I've never found it).

We did remove the skid plate and tried from underneath. The problem is that it's not working from there either. The fan and its guard is in the way from both the top and bottom.

And like I said, we got everything turning somewhat from the alternator pulley (able to use a torque wrench there for leverage), and we could hear air escaping, but nothing coming out of cylinder 1. Cylinder 1 obviously has compression normally because the relatively new plug I took out had burn marks indicating it was sparking.

What I'm getting at is that it seems like there should be an easier way to hand crank this engine in order to create more compression. Is there supposed to be a lot of resistance on the crankshaft pulley itself?

Also, is one revolution of the crankshaft pulley a full revolution of compression in all 6 cylinders? If so, then we should be able to find the TDC within one full turn (I'll probably have to do the screwdriver method).

Also, we are supposed to be turning it clockwise facing the engines, right?

I have a Haynes manual and it has less information on this procedure than anything I've seen online. It briefly describes finding TDC without any reference to the term TDC. Didn't see anything about manually turning the crankshaft either.

 

I found the other video where the guy films himself hand cranking the crankshaft pulley (video is P0305 misfire code video). Of course he took the fan out. Of course my buddy was trying to uninstall the fan incorrectly.

I guess next question is, how to take out the fan.

 

Taking the fan off on a Blazer requires some special equipment to hold the pulley while the water pump shaft is turned and is definitely not worth it just to find TDC#1.

It's really not that difficult from below. Just go buy whatever socket and length extension or adapter that you need to get on the crank pulley bolt from in front of the pulley (and behind the radiator shroud). What you buy needs to fit a 1/2" ratchet or breaker bar since the engine will be very difficult to turn with a 3/8 drive ratchet. If I remember correctly my setup is a deep 5/8 socket (3/8 drive) with a 1/2" to 3/8" adapter and a 1/2" ratchet - fits just right for me.

Yes, you turn clockwise as you are standing in front of the vehicle (like you was tightening the pulley bolt). It takes two revolutions of the crankshaft on a four stroke engine to go through the full cycle. Doesn't matter how many cylinders.

Especially if you are inexperienced, don't stick screwdrivers or anything in the cylinder. Too easy to munch that aluminum piston.

The easy way to turn the engine is with the starter, but you can't use the starter 100%. Have you buddy tap the starter a little at a time (and I mean as small of taps as you can) while you hold your finger over #1 spark plug hole. When it just starts to blow air past your finger, know you are coming up on TDC#1 so stop immediately and don't use the starter anymore. Now turn the engine clockwise with your 1/2" ratchet of breaker bar from below while you buddy watches the 2 timing marks on the pulley. One should end up about 5:30 and the other should line up exactly with the mark on the timing cover.

Drop the distributor in all the way with the rotor pointing to the #6 cast in the top, lock the distributor down, and you are good to go except for cam retard. Certainly it should start and run without SES light even if cam retard isn't set. But if you are not going to set cam retard, then don't modify the distributor hold down clamp. If distributor won't drop down all the way, turn the oil pump shaft to a slightly different position with a BIG and LONG screwdriver until it does.

Distributor does not hold any compression or pressure. You are just hearing air escaping past the piston rings.

As I told you before, Car Gauge Pro for Android along with the BAFX OBD2 Adapter (Amazon) is about $30. This will display cam sensor retard if you want to set it. Use the CMP Retard PID denoted with ** (double astericks). If you are an iPhone user - I believe you can do something with Dash Commander from Palmer Performance (they make an iPhone version) usng a WIFI OBD2 adapter, but know I have only tested Dash Commander for Android using Bluetooth OBD2.

Good luck

 

What do you mean by don't modify the distributor hold down clamp; does that include taking it off? if you're referring to the thing that bolts down the distributor (single bolt), I had to take it off to remove the distributor.

 

Please see posts #24 and #26. Modifying the distributor clamp is grinding the bolt hole larger, or in a way that will allow you to turn the distributor a little. I realize you are inexperienced and this is why we have been patient thus far - but frankly you need to start paying better attention if you want to motivate us to keep helping you. This has happened before. Better re-read everything carefully that has been said in this thread and make sure you understand it. If there is something that you don't understand please stop and ask now. Will be glad to help, but not to just repeat the same answers.

 

Just an update on the custom PID for CMP Offset in Torque Pro.

I set the Custom PID up per the instructions in the Torque Forum (above) but had to add "Auto" for the OBD Header in order for the custom PID to actually calculate a value. Indeed it then gave a CMP retard of 0.0° on my vehicle, but I happen to know from 4 other scanner softwares that my CMP retard is not exactly 0.0 and varies from 0.3 to 0.7 with temperature and RPM. These other 4 softwares always agree with each other. This custom PID for Torque Pro does not agree with the rest and I believe the Torque Forum is giving bad information.

 

The reason why I'm asking questions is because I'm on my own on this and I would prefer to know all the variables before I run into them.

For instance, I had a mechanic here. All I really wanted was to have TDC confirmed 100% so I could do the rest. All they did was line up the marks on the crank wheel with no interest in actually observing cylinder 1 for compression. Then they tried cramming the new distributor in when it wasn't lined up at all. So basically I now have to do it all over to confirm the compression, minus the cash.