am

I'm continuing putting back pieces togheter in this crazy project and i have two questions , well maybe 3.
1- for the distributor alignment could someone give me more details about the cylinder 1 mark , i checked on my cd version in the manual and it's not clear (bad picture)

2- about the cams alignment , do the cam gears have to align precisely centered with the marks ? on my engine the cyl 1-4 sprocket is 1/4 of an inch beside , the 5-8 is ok with the flywheel at tdc.


3- i read somewhere that a bolt of the tensionner is going thru the block in the coolant , is it realy in coolant ? because on mine oil is getting out of that hole and even if the engine is sitting since more than one year !

ViribusUnits

1. It's the only mark on the distributer. If your still confused, get the distributer cap, and find cylinder 1, and look in that region.

2. No. Get it as close as you can.

3. Yes, deffently coolent. Why was the engine setting? Blown headgasket maybe? Or maybe a busted oil cooler?

rjtw

Re 3) I just did the tensioner/pump/belt on my '83 a coupla weeks ago. One of the bolts on the tensioner itself dripped oil; none of these dripped water; however the bolt at the top of the tensioner arm (also keeping a bearing in place) dripped water.

Rick

PorKen

Re: #2

What fraction of a tooth is the cam off? 1/4" sounds like one whole tooth.

The engine will run much smoother, if the cams are as close as possible to the marks.

GlenL

So it's a '79 Auto?

1) There's a mark, or check for the #1 wire on the cap. On mine it's the plug most towards the front. Not critical as long as the wires match up right.

2) Likely won't be exact. Manual gives some indication of how to align them. Should be a little later (to your left when standing in front of the engine.) But if that's nearing a whole tooth, I'd go early. (to your right.)

3) Coolant? Don't recall that. Don't know that it matters. Use anti-seize on all of the tensioner bolts.

ViribusUnits

The arm for the tensioner, with the bolt that goes through that idler on the later cars. This is the only one that should leak coolent.

The rest shouldn't leak much of anything, expectin unless you pull the adjustment bolt out of the tensioner, in which case, you should get oil.

autochicago

Unfasten distributor cap. Lift grey dust cover (if it's still there) enough so you can see top edge where cap rests on distributor housing. There is a small scribed line on that edge marking #1 position. BEST way on any Bosch distributor, including these, is when cams and crank are lined up at TDC (0 deg on crank and both cams lined up at marks), tip of rotor points to that line, which, of course, will coincide with #1 plug wire.

In my experience the crank and cam marks are quite accurate, like usually within 1/2 a tooth. PorKen was right when he said 1/4" sounds a bit much. Double check things. Manually spin the engine a couple of revolutions (by the crank bolt, preferably not cams) and recheck lineup of the marks.

am

Thank you very much for your help.
1- i'll be ok with the distributor , it's the mark i tought it was , the job is done , i wanted to be sure.

2-for the 1-4 cam , if i move it one tooth it will be too much , so it should be ok

3- i'm a little bit scared of using anti-seize , what about teflon tape for the tensioner housing bolt ?

viribusunits quote : (Why was the engine setting? Blown headgasket maybe? Or maybe a busted oil cooler?)
The engine is out because i'm restoring the car , while it was out i did everything i could beside cleaning it , repainting the engine pit and changing the firewall sound absorber. The before and after difference is already pretty impressive at this point.
Thank's again guys for your precious help , i'm paying you a virtual beer !!!

In this project my motto :Slowly but surely

2V4V

am,

First, crank it through a couple of complete revolutions with a ratchet on the crank bolt and *then* see how it lines up. It might be closer, but I bet it'll end up being one tooth off. Ask me how I know this...

Don't forget, all of this stuff is referenced with the #1 cylinder at TDC - checking anywhere else in the rotation can give you inaccurate results. Same thing with tensioning the TB - MUST be at TDC1.

If everything is right with your engine, they should be really, really close to correct with the damper mark and the dizzy mark being perfectly on. The cams almost always end up within 1/4 of a tooth, once you tension the belt (which can sometimes pull that last 1/4 tooth delta out).

Greg

am

Hey Greg , i measured exactly how far the 1-4 cam was from the mark and it's 3/16th of an inch , i already did the 2 rev. many times and it stayed like this while the 5-6 cam and the crank are perfectly aligned with marks at tdc.
Thank's

Garth S

There is NO TRUE INDEX MARK on the block for TDC!!
The only fly in the ointment in all of this could be the mickey mouse red plastic pointer screwed to the water pump. There must be small variations in it's attachment, and possibly in the rebuilt castings it is attached to.
While in the early cars, the red tip extended through the center cover - the later cars 'improved' the center cover with a moulded pointer to cover the red index: the center cover is neither machined nor dowel centered on the block!

The short version of this is that a small offset in fixing TDC by the pointer is doubled at the cam cogs. At the moment, I don't know if you are going by the red pointer or center cover marker: In any event, move the crank ever so slightly (past TDC) and "split the difference" on the cam cogs. Does it look better? - It is unlikely you are a tooth off.
Regards bolts penetrating oil galleries and water jackets - the top right tensioner bolt penetrates the cooling jacket on some cars. I reinstalled mine using a teflon thread sealant - but a dab of GE silicon RTV works too: I'd do that prior to using teflon tape . The anti -seize may also hol;d out low pressure coolant. The pivot bolt on the pump may penetrate some pump castings, but not all: sealant here cannot hurt.

am

Garth s : to do my alignment, yes i used the red pointer that i put back on my rebuilt waterpump , and i have put the crank exactly at tdc , then i installed the tbelt over the 5-8 cam sprocket exactly on the mark again , it is when i arrive at the 1-4 cam that i have a difference of 3/16 of an inch. And yes i did the 2 revs !
If i turn the crank clockwise just to have an offset of about 1/16 of an inch i will then have the same offset everywhere but on the 1-4 cam it will be before and on the 5-8 it will be after. I think that to move the 1-4 one tooth will be way too much , what do you think ?
Thank's

Garth S

am,
There is another possibility considering your description:The belt may not have been drawn tight enough when installed. There is a small trick that is sometimes necessary ....to get maximum tension on the belt when first installing on the cam gears - before the tensioner is tightened.
With the crank at TDC, one threads the TB over the oil pump gear to the 5-8 gear: If you cannot pull the belt perfectly tight to engage the gear teeth with the cam on it's index mark, rotate the gear (27 or 32mm wrench) maximum 1 tooth clockwise to engage the belt correctly. then, counter rotate the 5-8 cam to the mark.
This assures no slack between TDC and the 5-8 cam and leaves the belt in tension.
Repeat the same trick on cam 1-4 after the belt passes the water pump: This is where it is most likely to have some slack in the belt, and could possibly cause the problem you are seeing. - ie., you are clockwise rotating the cams to meet the teeth, and then rotating counter clockwise that slight amount to the index marks assuring the belt is under tension (from the crank counterclockwise all the way to cam 1-4) BEFORE the tensioner roller contacts the belt.
It is easier to do than describe, but I have seen a belt tensioned with slack left between the two cams - and one cam appeared considerably off the marks. I hope that may help.

am

It did'nt work I tried and tried in many ways and the best i can do is the darn 3/16 of an inch on the 1-4 cam sprocket, one tooth is too much

Garth S

OK, I'm confused!! Can you post pictures of the belt and index points?
For what it may be worth, to view the 1-4 index point is very difficult because of the poor angle: when I installed a belt recently, I made a mark on the front of the cam wheel to indicate the index on the back: this made setting timing much easier, and more precise! The belt was on within 5 min, and the marks were within 1mm.
There may be another eay to confirm the timing: as the length of the belt is fixed , there are a fixed number of teeth. Then, at perpect cam timing, there must be a fixed number of teeth between the crank at TDC and the index of cam 5-8. Similarly, there must be a fixed tooth count between the two cams.
Does anyone know this data???
Lastly, do you have the correct tooth profile for the toothed wheels (Square tooth vs round tooth HTD? This would make a large difference in cam timing.