[Scott McDonald]

I have spent two-16hr days installing a new motor in my GT.

• I set the timing mark with the ball, and this with the cam sprocket hole @ 12:00.

• Then, I moved the distributor slot in the timing cover to look like it should in the manual.

• I stabbed the distributor with the rotor in the #1 firing position, and the slash in the rim of the distributor in line with the slot inside the timing cover.

• The plug wires were placed 1-3-4-2.

I tried to turn the car over. It wouldn't start.

I moved the distributor all the way counter clockwise, and the car finally started, but it was rapidly backfiring through the carburetor(pop-pop-pop). The backfire is as fast as a loose lifter knock for comparison.

I removed the distributor and repeatedly re stuck it with the same result.

I rechecked that my flywheel, #4 piston @TDC, and cam hole were correctly located.

The engine has a ported head, 2.2l valves, domed pistons, and an Irmscher Sprint-style cam. The vacuum advance is removed, and it's plates have been screwed together as well.

Does anyone have any idea what in the hell I am doing wrong? I made sure the piston/valve clearance was ok before firing it up, so I don't see how I could have bent a valve(but to be sure, I'll be running a compression check tomorrow).

If you have any, and I mean any idea for a solution, I am all ears.

 

[baz]

• I set the timing mark with the ball, and this with the cam sprocket hole @ 12:00.

• Then, I moved the distributor slot in the timing cover to look like it should in the manual.

• I stabbed the distributor with the rotor in the #1 firing position, and the slash in the rim of the distributor in line with the slot inside the timing cover.

• The plug wires were placed 1-3-4-2.

I tried to turn the car over. It wouldn't start.

some of the manuals have the diag of the poss for the cam wrong (there are some posts for it ) but i think all you need to do is move all the spark plug leads around 180 degrees new lead poss would be 4-2-1-3

 

[nobody]

Welcome to the 180 degree off club.

 

[kwilford]

I rechecked that my flywheel, #4 piston @TDC, and cam hole were correctly located.

The cam gear mark is aligned with the mark on the cam gear support when the #4 piston is at TDC of its firing position; the #4 cylinder valves should both be closed (and make sure that the valves have both been closed for a half revolution, such that #4 cylinder has reached the top of the COMPRESSION stroke, versus the EXHAUST stroke). At this point, where does the rotor point? It should be OPPOSITE the notch in the distributor, which is #1 on the distributor cap. As Dave has suggested, you might have joined the 180 degree club...

 

[jeff denton]

Yeah. What they said. The Opel timing setup is pretty strange. The instructions Gil at OGTS sends with his parts are very clearly written, but confusing to those of us who already know it all. I had to read them over and over! When the cam sprocket marks are lined up right and the ball is on the TDC mark it is fire time for #4! You have to rotate the crank another full turn to TDC again to make it fire time for #1. Weird, huh?

 

[jerseyopel]

wires

I tried to start my new engine the po had installed and after it popped I changed the wires 180 degrees.Engine fired right up then. Rule of thumb for an opel timing is: Do it like you think it should be and then reverse it, it will work every time!!

 

[GTJIM (R.I.P.)]

Once More - With Feeling!

The CAM timing is done with #4 (the rear cylinder) on the compression stroke as this is the ONLY position that the cam timing marks and the notches in the cam for head bolt clearance line up. This is the firing postion for #4 cylinder so to set the IGNITION timing on #1 cylinder the motor now has to be rotated ( with the cam drive connected) one complete revoulution until #1 cylinder is then in the firing postition and the distributor can be timed on #1 cylinder. The distributor is driven directly off the crankshaft and not the camshaft unlike most other motors ..........

Opels - don't you love them!

 

[Scott McDonald]

This swap has been more mentally/emotionally taxing than I would have believed.
Thanks fellas! I am at work now, so I will try this as soon as I get home. I will get back with y'all after I try. I thought I tried the wire switch as suggested above-to no avail, but I am so tired now I can't be 100% sure.

BTW-What does detonation sound like, and what does it do? As I sure as hell don't want to damage anything. Any other warnings of which you might impart some information?

Thanks! (I'm going to crawl under my desk now and get some sleep...)

 

[N61WP]

Detonation=Death Rattle!

Scott,

Detonation, or death rattle as Bob dennard called it, is the exploding of the fuel mixture before the piston is at TDC. Think of it like a sledge hammer coming down on top of your piston before it makes it to the top. Very damaging in extreem cases.

Keep us informed about the new motor!

James

 

[GTJIM (R.I.P.)]

"Death Rattle"

Like a sledgehammer hitting the top of the pistons is a very good description! Detonation usually only occurs under hard acceleration when cylinder pressures are at maximum. Once you have heard it the sound is unmistakable. An engine will survive a few seconds of "anvil serenade" - it is continuous rattle under hard acceleration that rapidly destroys the pistons. Just lifting off the gas pedal stops the damage - so keep an ear tuned for the sound!

What does it do? It makes the tops of the pistons look like the rats have been at them! The top ring land is often broken off and a melted track made down the side of the rings. Enormous pressures and very high temperatures are involved. Sometimes circular lumps can be literally "blown" out of the piston and the crown collapsed. Serrious melting is usually visible around the edges of the hole ...... as an old mechanic for circle track speedway cars I have seen the odd destroyed piston or two!

 

[tekenaar]

Ignition timing . . . one more time

The CAM timing is done with #4 (the rear cylinder) on the compression stroke as this is the ONLY position that the cam timing marks and the notches in the cam for head bolt clearance line up. This is the firing postion for #4 cylinder so to set the IGNITION timing on #1 cylinder the motor now has to be rotated ( with the cam drive connected) one complete revoulution until #1 cylinder is then in the firing postition and the distributor can be timed on #1 cylinder. The distributor is driven directly off the crankshaft and not the camshaft unlike most other motors ..........

Opels - don't you love them!

As I've said before, align everything as book (GTJIM) says but set ignition for #4 cylinder . . . no rotation required.

 

[GTJIM (R.I.P.)]

Originally!

As I've said before, align everything as book (GTJIM) says but set ignition for #4 cylinder . . . no rotation required.

I have a sneaking suspicion that is how it is supposed to be done and in the original German nomenclature the REAR cylinder was known as #1 - just like Jaguar does. The confusion has come about by the translation of the manual into English and the American perchant for numbering cylinders from the front of the motor. How is that for a hypothesis?

 

[Scott McDonald]

Well I haven't heard anything like that-yet. I did have one very loud backfire when trying to start it yesterday. The plugs were covered in a thick, black carbon coating, as were the piston tops. So, I cleaned the plugs hoping that may be the problem...it wasn't.

You guys have no idea how much sleep I've lost over this. I am so close. My wife asked me how it was finishing-up. "Finishing-up?" I said. Then I burst into a bout of almost uncontrollable hysterical laughter.

On a good note:

The valves were set- since it was warm, I figured why not. They are at .016"

It sounds very good, except for that rapid "pop."

I changed out the clutch, plate, throw-out bearing, and the arm that holds the clutch cable, as it was found to not attach to the rear adjusting stud in the transmission housing.

I changed the U-joints, and made some extremely hard rubber torque tube mounts.

This makes my entire drivetrain, suspension, shocks, interior...you name it-pretty much new. Once I get the little bit of cancer addressed, and a touch-up of new paint, I don't know what else could be replaced.

It is sad/good, whichever your perspective, but I can just about tell what bolts go where, just by looking at them.

Am I wrong when I'm thinking that for 1000rpm, I hear approx. 4-backfires through the intake. This would mean that 2 cylinders are receiving fire before the valves completely close.

If the earlier fixes don't seem to work:

Could the distributor be advanced a tooth or two, which is causing an early spark before the valves close? Or could cam timing be off a tooth or two? The head was thought not to be milled, but maybe it was, and advancing the cam 2-4 degrees be a possible solution. (I'm just trying to think of everything that is "detonating" in my head right now-so that I can make a flow chart to correct this nightmare).

 

[Gary]

• The plug wires were placed 1-3-4-2.

Am I wrong when I'm thinking that for 1000rpm, I hear approx. 4-backfires through the intake. This would mean that 2 cylinders are receiving fire before the valves completely close.

Is that 1-3-4-2 Clockwise or counter clockwise on the distributor?

 

[Scott McDonald]

Clockwise.

On another note, I just found out the car is not 180-out. I was so irritated, that I drove home in the rain to look @ the distributor during lunch.

With the engine popping, I had my cousin pull the plug wires one by one. Bingo, on the #1 cylinder the popping went away, and just pushed air through the intake. The valve was not closing upon closer inspection. After removing the valve cover, I now know why the popping was occuring. Why? There did not appear to be a lobe on the cam. I would think there to be crap in the oil, but there wasn't. What in the hell happened? The valves weren't too tight. I'm stumped.

What's my next step? Can I get the cam out without removing the head?

 

[jeff denton]

As you crank the engine over, are the rocker arms moving up and down, when the rocker arms stop moving down are they a bit loose on the valve stem? If the rockers don't move, you have a flat cam. If they don't feel a bit loose they are too tight.
Was that a new camshaft and lifters, and did you "break in" the cam right?

 

[N61WP]

Scott,

definitely look at the rockers moving as Jeff just suggested. If the engine hasn't ran yet, there is no way that you could have peeled the lobe off the cam by just cranking on it. I guess it's possible that the cam had a lobe missing from the get-go, but that's not very probable.

 

[Scott McDonald]

No rocker movement. The engine would and did run albeit with the popping from the #1 cylinder. The total time it ran was approx 20 min with the valve cover on it. The rockers were set cold, then set again when the engine was warm. I guess I never looked to see if the #1 exhaust was actually moving when I set it (it looked to be on the bottom). I thought the timing was off, and that I would set it when the rockers were adjusted, but once the rockers were adjusted, the pop could not be adjusted out with the distributor. I was sure it was a timing problem, and never thought to give the rockers another look. Boy did I feel stupid when my cousin had found that problem in no time flat.

That cam lowered the engine compression, so that it could run on Supreme Unleaded. Hopefully, another cam with similar dimensions can be found.

 

[nobody]

what were the cam specs?

 

[Scott McDonald]

Irmscher

Intk & Exhst:
lobe cntr sep = 104.2 deg
valve overlap= 28.5 crank deg

Intk:
valve opening= 14.3 BDTC
lobe centr= 104.4 ATDC
valve closure= 43 ABDC
Duration= 237.2 crank deg
Max cam lift= .30063 in-7.636mm
Net valve lift= .45094 in.-11.453mm
lobe 'area'= 25.68 in * deg

Exhst:
valve opening= 44.2 BBDC
lobe centr= 104.1 BTDC
valve closure= 14.3 ATDC
duration= 238.4 Crank deg
Max Cam lift= .29976 in-7.614mm
Net valve lift= .44965 in-11.421mm
lobe 'area'= 25.78 in * deg