Doing cam timing when engine lock up?

[Oheggem]

Hoping for som e advice here.

I had the left cam tower off in one peice without doing anything to the right side and now on reassembly i came to a stop on 2 things i can`t search for.

I put the cam tower on again with all valves and rockers in place and had to turn the crank a bit with a loose chain. Now i got the cam mark to the top and the crank at TDC and on Z1 mark. I put the the shims sprocketmounted the chain and such on and the chain wheel the tensioner is pressing against. Without the tensioner. I tried to go 720 to check if it where all good but the chain got tighter and sort of jumped a tooth or something. i kept trying until the engine locked up. Is the chain not mounted properly on the crank?

Another part i can`t figure out. Found it somewhere in the chain housing but can`t seem to fint a spot for it. It`s the part all the way to the right. Next to the woodruff key.


Any clues

Thanks in advance

[safe]

You can't turn the engine without the tensioner, the cam will get out of timing,
Go back and reset everything....and yes the chain can jump of the crank side gear been there.

[Walt Fricke]

That little piece is a mystery. Is it round? Square? There is a pin in the idler arm holding the idler sprocket in place, but I think it is longer than that. Could it be a failed piece from a chain? Unlikely, but were it in my motor I'd be worried also.

When you have the cam out, or move things around without any tension on the chain, it is easy, especially on an engine stand, to have slack pile up down by the intermediate shaft gears. At some point, the slack will jam, and then jam tighter. Putting tension on the chain while rocking the crank will usually allow you to pull the jammed slack chain out. Has worked for me, anyway.

It is a good idea, once you have things back rotating, to use a light and mirror (or a borescope - they are now down in the $100-200 range) to take a look at the IS gears and the chain, to make sure the chain is properly engaged.

[Oheggem]

Thx for that. I ditt know i had to install the tensioner. Seems logical though

That little pin is rund. Fant seem to find out where it gods. I found it or i think it fell out from somewhere when i dissembled the cam sprocket ett. Weird

Back to timing the cams again the guys

[WERK I]

Cam Tower oil line plug? #22 on the illustration.

[Oheggem]

Dose not look like that noe. This pin is just straight and completely round. I'll check though

[Oheggem]

Thx for the tips guys. got it all working now.

Timing the cams and thought i`d check where the right cam was set so this was the procedure.

Set crank at Z1TDC mounted the z block and metric gauge. Turned crank 360 while watching gauge. it turned one round and stopped at 65. that means 1.65mm right? this sound ok? can i adjust the left one at that?

[Flat6pac]

With stock cams, I think I was setting .8mm as spec. What cams are you running?
Bruce

[Oheggem]

they are stock cams i think. Right side has not been loosened and is set at 1.65 that is why i set it at that. what will this affect?

Also i`m going to struggle to retorque because the cam is completely round and there`s a bolt and shim instead of the big nut so no way to use the crowfoot tool. i need to find another way to lock of that cam to torque it down.

[Smoove1010]

For my '87 3.2 it's 1.25 mm. From what I've read, the correct setting seems to vary from engine to engine. As for the reading, it depends on the gauge you use. On mine I preloaded about 7mm, zeroed the dial. Mine is a 10mm gauge, each rotation of the dial is one mm.

As I turned the crank and approached 360 degrees, the dial indicator spun backward as the valve was depressed by the cam. The dial moved backwards one full rotation (one mm) then stopped at .75, so the full movement was 1.25 mm.

If your dial indicator moved backwards, your .65 may then indicate movement of .35. If the dial spun back a full rotation, then you've got 1.35 of movement.

Fully understanding your dial indicator and finding out the right setting for your engine are necessary to complete this. I'm sure if you posted a pic of the dial indicator you'd get good guidance here.

I hope this makes sense and is helpful.

GK

[Smoove1010]

Originally Posted by Oheggem

they are stock cams i think. Right side has not been loosened and is set at 1.65 that is why i set it at that. what will this affect?

Also i`m going to struggle to retorque because the cam is completely round and there`s a bolt and shim instead of the big nut so no way to use the crowfoot tool. i need to find another way to lock of that cam to torque it down.

Sounds like you need the cam holder bar:
Part #: PEL-TOL-P237

[Walt Fricke]

Ohe - you have neglected to tell us what engine this is. The SC and 3.2s use the same cam, and over the years Porsche's specifications for where to set the cam ranged from a low of 0.9 to a high of 1.7 mm.

Advancing the cam (higher number) increases torque, and retarding increases horsepower. Bruce Anderson (RIP) asserted that on the 3.2s Porsche went back to a setting about in the middle, and I've heard guys who experimented and used a chassis dynomometer say that is about right. Not a huge difference either way.

1.65mm sounds like it is within range, and since you don't know what cams this motor has, and I guess it ran well before you got to working on it for some ailment on one side, so it makes sense to use 1.65 as a goal.

You have been given the advice you need already: the special tool (alas, you can't just use some kind of regular tool for this the way you could on an earlier type cam), counting full revolutions of your dial indicator, and knowing which way it is turning to interpret the readings.

There is a better dial indicator now available at relatively low cost: the digital indicator. These are switchable from metric to inches if you want, and give absolute readings (no counting revolutions so no getting that wrong). And have a zero button as well. I commend them to all of us who don't do this often - less techinque/things to remember involved, so less chance of a mistake.

[Oheggem]

Ah sry about that. Engine is 79 3.3 turbo cams are standard. Checked the partnr now. It has some upgrades like the k27 turbo and others i`m not sure of since absolutely no papirs followed the car.

The dial gauge is metric and is dialing the wrong way but it turns one 360 and stops at 35. backwords that will be 65

Thx for the info there. It did run pretty well but had alot of turbo lag and didn`t idle very well.

Dammit. I missed that bar tool when i got a big parts package from pelican last week!! Need to find other ideas to lock that down. Thx

[Walt Fricke]

I thought that the cams in '79 were still the big nut kind, not the bolt kind. Doesn't mean these are not turbo cams. The '82 US SC motor I bought used surprised me by having the big nut - this after I had purchased the tool for the bolt system (about 15 years later I finally needed it for another motor).

If your cams were timed at 1.65mm, they are way out of spec for stock turbo cams for that motor.

Here are the specs, along with numbers which ought to show up on the end of the cam:

[Oheggem]

Its marked with 930 143 03

Cou8ld not find that number on the list....?

[Flat6pac]

142 is turbo cam
147 and 148 are SC
Bruce

[swade]

Oheggem,

Where are you? You could borrow mine for a short time. PM sent with phone number.

Wade

[Oheggem]

I`m in Ålesund Greatly appreciated Wade!!

"142 is turbo cam
147 and 148 are SC"

I found out i think that 930 143 03 is from 930s from 84 if i`m not mistaken. However the only other number that match are those in the link below. I think it`s weird though to change cams to a later model if no modification is done by it. Anyone know if the 84+ has higher lift or something?
Racing cam part number wthe R

[safe]

A good strategy is usually to track down previous owners and talk to them, they are usually quite chatty about their old cars.

[Flat6pac]

The last cam numbers change because the 46mm nut and the 12mm bolt.
All turbo cams have the same values.
Bruce