308 2V Cam Locking Tool, loan or sell?

I'll be making a production run of the tools in a couple of weeks. Click on my name and then click [send eMAIL to Verell] if you want one.

Price is $95 each/$170/pair.

For pictures see 4Webers posts in this thread:

http://ferrarichat.com/forum/showthread.php?t=40071

 

forget it ---

Cut (4) pieces of blank, white index note card (with no ink / lines) to about 1/2" x 1". Remove the cam covers, remove the cam shaft journal bearing covers second away from pulley --- only one per camshaft, wipe off excess oil from inside of cap and camshaft journal bearing surface, place the card piece inbetween the cap and the shaft and torque to 50% of full spec value. This will effectively "lock" the camshafts against any rotation.

Cost = 3 cents...

 

sure if you've removed the cam covers, but for those not wanting to go that far and only replace the belt it won't work.

not advocating cutting corners here just the observation of past belt changes.

 

Unless you are going to use a degree wheel to align your cam timing, I STRONGLY recommend removing the cam covers. There are 2 sets of timing marks on the 308 2-valve engines --- one is on the cam covers, and the other is on the cam journals (these can only be seen with the cam covers removed). The marks on the cam covers are notoriously inaccurate and are provided merely as an inspection reference to ensure, at a glance, that the timing is not dramatically off --- jumped pulley tooth, etc. The marks on the cam journals are very accurate and can be used to set cam timing --- the factory uses these marks to set the timing themselves (they don't take the time to degree wheel each engine leaving their engine shop). I have personally cross-checked the journal marks on my '81 308 against a degree wheel and found them to be within 1/4 degree agreement --- more than precise enough for this engine.

 

this has been discused so many times, but there are still those who feel it's safe to change the belts without re-setting the cams. i'm not going to argue pro/con on the subject.

i've never been a fan of clamping down on material in a journal as it risks scoring or damaging the journal, as an engineer i'll say it's not a good idea. it also raises the stress to the cap as the journal dia is now being forced to change. and this is especialy hard the caps/journals when that same method is used to loosen the cam bolt on the pulley. take the time to remove the cam then bench it and remove the pulley, since your going that far it's a great time to check the valve shim wear as well.

 

In general, I tend to agree with smg2. I don't in general recommend using something under the cam caps, especially to novices.

In some of my early Fchat posts I discussed using it, but since then I've become much much more cautious, especially since there are now a lot more people with relatively little experience doing their own service.

The cam-cap clearance on engines in good shape is only 0.003" - 0.004", and on engines with a lot of wear it's still usually only 0.005" - 0.007".

Banknote and other thin paper is about 0.004". If you absolutely feel you must use this technique, then use a single layer of paper (doubled if engine has lots of wear) that you have MEASURED with a micrometer to verify that it's only 0.001" or so thicker than the gap you're filling. Only tighten the cam cap enough to keep the cam from rotating. This is generally finger tight or a little more.

Especially don't use index card, it's about .012" thick. Matchbook covers are even thicker. Using either has been shown to bend or more often break cam caps (search the Fchat archives).

Also, make absolutely sure you've removed the paper as running even a short while with a piece of paper in place will damage the cam and/or cap as there's no lubrication.

Don't even think about using the paper under the cap technique to lock the cams down enough to break the cam gear bolt loose. The break-away torque for these bolts is on the order of 100-150 ft-lbs or more! Trying to resist that amount of torque using a piece of paper about 1/2" away from the cam's centerline just doesn't make sense!!!

As to using cam locks, they should only be used if you're certain that your current cam timing is spot on. However, the newer 2V engines do have very small accurate timing marks on the cam pulley flanges. My 2V cam lock tools have matching marks that can be used to verify the cam timing.

 

Steve,
You are welcome to borrow my 2 valve cam locks. Only problem is Verell borrowed them after we built them to do my 308 major 2 years ago. He used them as a pattern to make his....and I never saw them again!! ;-)

So if I ever see them again, I'll loan them to you....

Just giving you a hard time Verell!!

Birdman

 

So, suppose novice is removing the cam to replace the seal. Novice has read many posts on f-chat and understands those caps need to be removed and installed evenly and slowly about one turn at a time. What's the right way to make sure things stay lined up as the caps are tightened (2V engine)?

Seamus

 

seamus,
there are two ways in which that seal is coming off the cam, the first is to remove the cam and slip it off the back. the second is to remove the pulley and slip it off the front. now for the those with the smog pump you'll have to make a choice, smog pulley or cam pulley.

i'd bring each bank to TDC and remove the cams, one bank at a time on-off. so setup the easy one fisrt, bank 5~8 and get it at TDC check to see that your all lined up then start the slow methodical cap removal. each cap has two nuts and two belville washers. the washers in profile look like bowls, when reinstalling face the bowl down.

the 2v at TDC will keep the cams from twisting out of time on you when reinstalling. i find it easier to go a little at a time and keep checking the marks to make sure i'm still good. once it's seated then do the belt procedure.

WARNING! once the cams are back on DO NOT turn the crank with out the belt back on the cams.

once again another great time to check shim wear.

please refer to the WSM i've only highlighted the procedure.

 

I'm thinking smog pump pulley given I have heard the cam pulley is 'fragile'.

Wouldn't the 1-4 bank be the easy one? My plan was to get my learnin' on the bank at the rear of the car.

So it sounds like with the valves for two cylinders closed things tend to stay in place. My concerns are regarding the 5-8 bank at TDC and the cam marks for that bank but like a lot of things discussed here sometimes it becomes clear once you're in there. I'll do a lot of looking once I have the valve covers off. I am getting close -- the A/C is almost out -- I am at the point where I need to remove the studs to help get the rear belt cover off.

Seamus

 

If you get stuck and need to buy a cam locking device I have one left. Fits all 2 valve 308s. This one device does both sides. The price is $45.00 US plus shipping. If interested send me an email and we can work out the details.
axel
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Okay, officially confused now . I've got the cam covers off. I can see that all *four* cam marks are lined up properly with the engine at PM1-4 which is what I expected.

What I did not expect was the idea of rotating the engine at all during cam removal and replacement -- even for the front bank.

Maybe I'm missing something?

Seamus

 

sorry, yes when PM1-4 is at TDC all four cams should be lined up. what i found though was that bank 5~8 not being at TDC the cams would pop and rotate out when trying to re-install, if PM5-8 is at TDC then it's easier to get them back on.

now i did assume alot in that one would mark how they go back, i used a scribe and marked the cams on 5~8 when at TDC since the factory marks were not in sight at that rotation. the flywheel is marked PM5-8 for reference to.

but if you've never done this or this is your first 'cam' related timing job for any engine. then i'd caution against it.

set it to PM1-4 and remove the cams, both banks. watch carefull on 5~8 as it will try and 'spin' on you. the caps are also numbered and marked for right side up. DO NOT missplace thier location as they are reamed and set in place.

sorry to confuse.

 

No problem. I had an idea what you were talking about but knowing how careful one has to be I was concerned about rotating that bank. I have done cam removal and installation on motorcycles, but, yes this is my first cam related job on a car (outside of checking valve clearances). I *really* don't want to muck it up!

So, I will stick to the straight and narrow as much as I can.

Thanks for clearing things up.

Seamus

 

DAVE HELMS ----- Are you out there? What's your opinion / experience with this?

All right, now I'm getting a little paranoid...

Warnings against using a piece of paper (or any other material) clamped underneath a cam bearing cap (or even several caps) make sense --- it certainly could be dangerous, in theory.

But, does anyone have any real empirical evidence that using this technique has actually bent or broken a Ferrari bearing cap? I mean has anyone actually done this and then verified with before and after measurements that the cap was permanently deformed?

I ran a quick finite element model on this scenario, and it predicts that a bearing cap (modeled to the 308 2-valve design) can be deflected up to 0.013" before plastic deformation can possibly occur (yield stress exceeded, even for the softer AL casting alloys).

So, even with a line-to-line fit between cap and cam journal, you could stick a piece of soft material (i.e., paper) up to 0.013" thick in between, clamp down to full torque, and still not do any harm with respect to bending (ignoring the idea of scratching the surfaces, etc.) the cap.

With nominal clearances to factory specs or beyond, you could use an even thicker piece ---- adding thickness (over the 0.013") equal to the actual radial clearance measured.

 

Dave has already weighed in, see this thread in the old fchat:

Help - on replacing front cam seals 328/3.2

http://70.85.40.84/~ferrari/discus/messages/256120/281134.html

In this thread Dave reports having to deal with a rash of bent cam caps. His cam clearance numbers & paper thickness numbers are consistent with the ones I posted earlier.

CAVEAT: As I said earlier, I've changed my recommendations since I made that post. I no longer recommend the paper method as it's too risky. It's also why I'm building 2V cam locks & have a 4V cam lock design in the works.

 

If you really must use cam clamps, and there is a good thread in the 348/355 section about why NOT to use them, the easiest thing is to make some. Buy a Nylon cutting board from Target or Kmart, and get out your trusty jigsaw and start cutting. Then grab a drill and drill a hole in each piece. Finally, stick a bolt or screw through the 2 holes and voila! You have your own cam clamps.

Total cost <$10. Look on wife's face as she sees you sawing into a cutting board that she thinks you just took from the kitchen? Priceless....

 

I have read a lot about this problem both here and on the old Ferrarichat.

The key for me is that I am *removing* the cams, which makes me question the value of any locking devices -- maybe this is the first place I am missing something?

Given that, then, if my 5-8 bank cams want to wander what is one to do?

If that is not enough I need to figure out how to safely vice the 1-4 exhaust cam so I cam bust the ring nut for the air pump pulley off with an air gun. Or, maybe no bother and just with the grace of the air gun I am golden?

Seamus

 

"The key for me is that I am *removing* the cams, which makes me question the value of any locking devices -- maybe this is the first place I am missing something?"

Agreed. I thought you said all your marks were lined up with the caps, on all four cams, right? Then you're set. Take the cams out, slip the seals off the back, if you need help getting the air pump ring nut off, come by the shop and we'll use the proper tool and it won't take a minute.

-Peter (not sure how I've successfully done fifty-plus 2V major services in twenty-five years without cam-locks... <very big grin>)

 

Thanks, Peter. Very fortunate to be just a few miles from your shop.

Seamus

 

Even if you're pulling the cams, the cam locks come in handy to lock the cams in place while you're re-pinning the cam gears & reinstalling the belts. Especially if you have to figure out a new pinning arrangement because the car came in with one or more of the cams mistimed.

Yes, you can certainly do the job w/o them, especially with experience. However, it's easier & less time with them(been there).

 

How many sets do you want?

JM
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Hah! I spy an M3 (or some other bimmer) lower control arm back on that table! Did you replace them for aluminum ones?

-Peter

 

yep. How many cool things can the true car guy see in this pic?
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