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Timing chain alignment & distributor position
https://slantsix.org/forum/viewtopic.php?t=54641		 Page 1 of 2
Author:  oracertified [ Sun Feb 16, 2014 6:20 pm ]
Post subject:  Timing chain alignment & distributor position
Good news!: I just prevented a 1974 Satellite from being sent to the scrap yard. :D It has a 225 cid 3.7 liter engine and the previous owner attempted a head gasket replacement. He stated that he could not get it started after the replacement.

I noticed that the wires were in the wrong position on the distributor cap. I put them in the correct position according to the book. Now when I try to start it, it spits out the carb. (POP!). I suspected the timing chain and pulled the cover. However, the dots line up together as it should. ( No big deal because the timing chain had a lot of slack in it and its easy to do. )

Here is the question:

I have the dots lined up but the rotor is under Spark plug number 1. I have read some listings that state that it should be under cylinder #6 which is 180 degrees off. I did call the seller and he told me that they did pull the distributor during the head change.

My next course of action would be to lift the distributor and rotate it so that its under #6.

Is that correct?
Author:  ceej [ Sun Feb 16, 2014 6:45 pm ]
Post subject: 
Is the engine on the compression stroke approaching TDC when the marks align for cylinder #1 or #6? They both are at TDC at the same time. Where is the cam when the marks align? Both valves should be closed, and on the upstroke, the intake valve should have closed approximately 30-35° after BDC based on correct rotation.

What are you basing TDC on? Have you verified TDC on the damper? The mark may not be accurate. Verify the damper mark is correct, otherwise, put a mark on the damper so you'll be able to time the engine.

If the distributor was stabbed wrong before, you could be completely off base. Find TDC, find fire on #1, and put the distributor in to support the position of the engine.

CJ
Author:  slantsik [ Mon Feb 17, 2014 3:55 am ]
Post subject: 
May I also suggest you triple check the leads are in the correct firing order .
clockwise looking down at distributor 1-5-3-6-2-4

you need the rotor arm in the distributor to point directly under the #1 cap tower, when the #1 piston is at TDC position on the compression/power strokes.

This will give you ~0 degrees spark timing. turning the distributor body anti- clock wise will advance the timing. There is a bolt under the distributor body for extra adjustment.

checking the TDC mark with piston position, before doing the above can save much frustration.

forget about the dots for now. just make sure both valves are closed at #1 TDC.
If the valves are both slightly open , at #1 TDC you are at the top of the exhaust /intake stroke ,you dont want the spark to fire there!!!

I have my distributor set up, so the bolt is at the top end of the adjustment slot at 0 degrees spark advance.

Hope this helps some.
Brendan
Author:  oracertified [ Tue Feb 18, 2014 4:52 pm ]
Post subject: 
I found TDC on 1 by spinning until crank was lined up and the mark on the harmonic balancer was on zero degrees. The camshaft socket mark was 180 degrees away. At that point the rotor was under 6. I then lifted the distributor and turned it so that the rotor was under cylinder 1. I did check and the valves were closed on cylinder 1.

Then I spun the engine until the dots were lined up to confirm that they were set correctly. Please see the image below and tell me if it looks lined up to you. The red line that you see is a line from the photo editing software .

After the engine did not start I finally checked the compression and it is extremely low. Cylinder 1 is 15 lbs, and the others range from 30-35 psi.

My next step is to pull the head to see if the seller messed up the head gasket replacement. But it would have to be pretty bad .
Image
Author:  Charrlie_S [ Tue Feb 18, 2014 5:08 pm ]
Post subject: 
Did you check the valve adjustment? Were they readjusted after the head gasket replacement? If they are too tight, it could cause your problem.
Author:  Reed [ Tue Feb 18, 2014 5:26 pm ]
Post subject: 
(1) There will be a timing mark at 0 on the timing scale when both the #1 and the #6 cylinder are at TDC on the compression stroke. You need to verify that you have the spark plugs firing at TDC on the compression stroke rather than at TDC on the exhaust stroke. It is possible that the distributor was timed correctly and you put the rotor 180 degrees out of phase from where it should be.

To verify that you have the rotor pointing at TDC on the compression stroke, you need to pull the valve cover and rotate the crank by hand while watching the #1 intake valve. Rotate the crank and watch the valve open and then close. Now keep turning the crank until the timing mark reaches 0. You now have the engine at TDC on the compression stroke. Verify that the rotor tip is under or slightly after the #1 plug tower on the distributor cap.

(2) Ditto on what Charrlie_S said about checking the valve lash.
Author:  oracertified [ Tue Feb 18, 2014 6:14 pm ]
Post subject: 
I just spun the motor with the valve cover off. I monitored Intake valve #1 and watched it open then close. The harmonic balancer was then placed on zero. I pulled the dist. cap and verified that the rotor tip was under spark plug wire number 1.

I then wiggled the rockers and there was plenty of play to allow full closure of both the intake and exhaust valves.

Next, I spun the engine and I still have only 10-30 psi.

Some people have mentioned stuck rings (The engine has not been run in 3-5 years.

In case I mention it, the seller did break off a bolt in the head between cylinder 2 and 3. But I assumed that the engine would still start and or have some compression on the other cylinders.

Well, I will pull the head and get it "reworked" If I can find a local shop.

Thanks for the help folks. I am just trying to keep this one from being scrapped. I have thought of changing it to a 318 but this site has got me very interested in using the slant 6 if I can cost effectively pull it off.
Author:  Charrlie_S [ Wed Feb 19, 2014 1:23 am ]
Post subject: 
Quote:

Thanks for the help folks. I am just trying to keep this one from being scrapped. I have thought of changing it to a 318 but this site has got me very interested in using the slant 6 if I can cost effectively pull it off.
It will be less expensive to repair, or replace the slant, then to swap to a 318.
Author:  slantsik [ Wed Feb 19, 2014 3:12 am ]
Post subject: 
Did you do compression test with all spark plugs out ,throttle wide open and fully charged battery?
If so , next test may be a leak down. If no leak down gauge is available , you can still pump some compressesd air into the cylinders,(with both valves shut ) and listen to where the leak(s) are coming from.
ie from the intake/carby = intake valves leaking
from exhaust pipe = exhaust valve leaking
from oil filler hole= rings
bubbles from radiator = head gasket
etc
If no leaks are easily detected , your.camshaft may be ground/installed incorrectly.
sounds like you tspark timed the engine properly. Did you confirm you have a good spark?
good luck and let us know what happens.
Author:  Reed [ Wed Feb 19, 2014 8:28 am ]
Post subject: 
Quote:
I just spun the motor with the valve cover off. I monitored Intake valve #1 and watched it open then close. The harmonic balancer was then placed on zero. I pulled the dist. cap and verified that the rotor tip was under spark plug wire number 1.

I then wiggled the rockers and there was plenty of play to allow full closure of both the intake and exhaust valves.
OK- rotor where it should be.
Quote:
Next, I spun the engine and I still have only 10-30 psi.
Oil pressure or compression? Is this with the engine running or just spinning from the starter? If you are talking about oil pressure, that's not bad for just spinning the starter. Heck, that's not bad for a running motor, either.

If you only have 10-30 PSI compression, I have to wonder if you are using a thread-in compression tester or the kind with the rubber tip that you must manually hold in the spark plug hole while cranking. The thread in compression testers are much more accurate than the rubber tip variety. I have had many false low readings using the rubber tip style compression gauge. The gauge has to be perfectly sealed or you won't get a true reading.
Quote:
Some people have mentioned stuck rings (The engine has not been run in 3-5 years.
Could be. BUT…..
Quote:
In case I mention it, the seller did break off a bolt in the head between cylinder 2 and 3. But I assumed that the engine would still start and or have some compression on the other cylinders.
That is fairly impressive considering the size of the head bolts.
Quote:
Well, I will pull the head and get it "reworked" If I can find a local shop.

Thanks for the help folks. I am just trying to keep this one from being scrapped. I have thought of changing it to a 318 but this site has got me very interested in using the slant 6 if I can cost effectively pull it off.
If you are using a thread in style compression gauge and still only getting 10-30 PSI compression, then pulling the head is a good idea. Snapping a head bolt of suggests to me that the previous owner was clueless. I would get the head inspected for warping and get that broken bolt out of the block.

If you are using the rubber tip style compression gauge then I suggest getting a thread in gauge and trying again. Did you squirt some Marvel Mystery Oil into each cylinder and then try the compression test?

And Charlie is right again- it is nearly always cheaper to build and upgrade a slant than it is to install a 318.
Author:  emsvitil [ Wed Feb 19, 2014 4:36 pm ]
Post subject: 
The Schrader valve for the compression tester may have been changed to a tire valve.

The Schrader valve for compression testers is not the same as those used for tires even though it looks the same.

The tire valves use a stronger spring to shut the valve.

So when used in a compression tester, the air pressure has to overcome the spring pressure first, causing a low reading.

They have special low spring pressure Schrader valves for compression testers.

Hook up a hose from an air compressor and see if the compression tester reads the same. (you need to improvise to hook things up)
Author:  oracertified [ Wed Feb 19, 2014 6:01 pm ]
Post subject:  Compression tester and pulling the head
The compression tester is the screw in kind. It is brand new from Auto Zone.

I think the guy was clueless when changing the head gasket and if he did not bolt it down in the right pattern he may have damaged the head.

Since I have to pull the head to remove that bolt I am taking the head to the local NAPA machine shop. I chose them because I use a local auto repair shop and simply asked them where they send their work. In fact, I am tempted to pull the engine and send the whole thing. But the car only has 64,000 miles on it and the bottom end may not need work.... I believe the mileage to be true because of the condition of the seats and pedals .

Incidentally, I may want to put a cam, headers and a 2 barrel on it. Any suggestions?

Again, thanks for everyone's help.
Author:  oracertified [ Fri Feb 21, 2014 4:12 pm ]
Post subject:  Confirmed that the head is bad.
UPDATE:
I dropped the head off and he demonstrated that the seals on the exhaust valves would not hold any pressure. Then, today he called me today and told me that the head was cracked where the bolt broke off. I believe it because when I unscrewed the last bolt, the head lifted itself 1/4 of an inch.

So, I am ordering a new head. I want a decent camshaft for this vehicle to make it sound intimidating . Any ideas?
Author:  Reed [ Fri Feb 21, 2014 4:21 pm ]
Post subject: 
Is your goal for the camshaft solely a "aggressive" or "lumpy" sound or are you looking for some kind of performance out of the cam?

Do a search in the board about the Erson RV 15 cam and send your cam off to Oregon cam grinders to get reground.
Author:  oracertified [ Sat Feb 22, 2014 6:40 am ]
Post subject: 
If I had to put it on a percentage scale
75% aggressive sound
25% performance / mileage
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