348 Engine repair thread

The new pulley is definitely better and beefier and 1/2 the price. Just needs a 3mm steel spacer.

Sent using FerrariChat.com mobile app

 

OK so I made the first set of spacers. Unfortunately I used the pully ID as a reference. The pully is press fit so the OD of the shaft is slightly larger. The spacer fits but you have to press it on. I don't want the spacer to be overly snug so I have to make them again. Another issue is the woodruff key is not full length so a spacer would slip off the back of the key and dangle on the shaft. So I will make them again slightly lager ID than the shaft like .04 mm larger so it should snug on but not need to be overly pressed. Then slide it on just over the key to seat it square, put the pully on, tap it on partially then tack weld it to back of the beefy snout. Slip it off then weld it permanently. You can see the back of the snout here. With the OD chamfer on the pully snout the weld should be good after you sand off the plating of course. Need to double check the OD and tap pully on and measure seating depth with exposed shaft then do some math etc. I don't want to make these things 4 times, it gets expensive making 10 at a time.


Image Unavailable, Please Login Image Unavailable, Please Login

 

Ahhh, well the key is in there good appears to be press fit, it does not gently lift out, at least not on mine, getting it back in square could also be an issue if removed, its really freaking tight. To get the spacer on the shaft it has to be keyed really, its not big deal to make that.

In theory if it is just a spacer and rests against the bearing then no need to tack it yes. One issue is if it sits back, and the spacer slides off the back of the pully key, then is there a risk that is spins at a different rate as you ramp rpm's etc and that could cause some shaft and bearing face wear.

This is why I have to put the pully back on, measure the actual seating depth, measure the bolt stick out, remove it and determine if it indeed sits against the bearing. I think it does as the pully had marks on it from the bearing race.

 

Its odd, if you look at the key it appears the key has a lip on the back, that means the pully likely never goes beyond that. If so then it does not seat back. It looks like a lot of space there but remember there is pully covers there when assembled. Task 1, seat the original pully and measure how far back it sits. Not tacking it would be great. Not too worried about the spacer spinning at a different rate the fit would be snug and it would be pressed between 2 surfaces.

 

Re-measured, should be ready for pick up in a week. It should slide on with slight friction and rest against the bearing race but not touch the seal and be the correct thickness which if anyone cares is 3.13 mm. Hopefully it will work and wont need to weld, one reason to weld is so you can get it back off. Have to balance it. Make it too loose and it can slop around too tight and you can't get it back off when its pressed against the bearing. Like baby bears porridge, it should be just right. Using 1018 steel.

 

Ok so new spacers are here. Yes you can pop out the woodruff key but it may either be stuck, one may not want to or what not and the cost to make the spacers with or without the key way is identical so I made them with for others ease. I made 10. The new pully is now identical to the old one measuring stick out. The spacer's JUST fit as I felt it important to get close tolerance as pressing the spacers on may make it hard to get them back off the bearing face. You'll swear they don't fit, but they do. The fences are thicker on the new one so its hard to tell by eye but my Mitutoyo caliper using depth of measure says they are within .02mm of each other, but the factory pully is not precisely machined as you get different measures from here or there in the pully breach. In addition the mating surface is the same as the pully end which is chamfered. I could have increased the contact area as you can see on the bearing but I left well enough alone. I recommend deburring the edges, they are sharp. Then a light coat of rattle can. Anyhow, check, done one better engine coming up.

BTW not sure if you noticed but when looking for the older model used pulleys, the fences are all jacked and bent. ANY they cost more than the newer better beefier pully. No way would I put that on. In fact if I actually SAW my pully when I bought the car and had a major done I never would have put it on.

Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login

 

Makes sense.

Sent using FerrariChat.com mobile app

 

Tha'ts exactly the issue. Its also possible it will always apply pressure due to rotation forces even spaced out more. I too see the pully as a major service item as mentioned early on in this post.

The exact measurement of my spacer shows .18mm further stick out. Pully difference is 3mm my spacer is 3.18 mm. However these are not precision machine fit so when its on the measurement varies as I found. Some spots its more some spots its the same. The new pully has a fence twice as thick. Measuring the space between the fences would be good a well as that with belt wear will give the offset needed.

 

Little work while I wait for my heads. I got my old woodruf key out and put a new one in, of course the spacer still fits like a glove. Made some fittings to pressure test the cooling system, got larger flywheel and altered the flavor inserts and seat to fit the 348 bolt nice and snug perfectly centered. Figure I might as well put the rear stainless brake lines on. Replaced all the solenoids. There of course is one you can't get to with the manifold on so may as well now. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login

Sent using FerrariChat.com mobile app

 

btw the centering flange for the timing wheel, open it up one step on both sides with an SAE stepped drill bit. Then the bolt can be threaded into the centering flange using a socket as the aluminum flange is very soft, it feels like 5052.

For the PVC fittings, drill is slightly smaller then force schrader valve threads into the PVC with a box wrench on the schrader. I added JB weld to prevent it from popping put under pressure, probably not needed but why not. The smaller hoses can be plugged with 1/4 inch extensions.

 

Water pumps in good shape and has no play so it goes into spares bin, but as long as I'm replacing everything may as well replace it. I plan on absolutely ruining with mileage and I do not want back of the head nagging "what about..."
Image Unavailable, Please Login

Sent using FerrariChat.com mobile app

 

The idler pulley is pretty easy to pull out you just add an additional spacer behind it that one's pretty straightforward. The tensioner however is another problem bringing that out is a bit more difficult due to the housing.

I always assume the outer fence came loose because people putting the belt on and off would tug and pull and apply pressure against that outer fence trying to remove the belt.

And by the way not using a spacer with a new pulley would likely be catastrophic due to belt pressure on the front fence. The old police no longer available you can buy a refurbished but it's more than twice the price of the new better pulley.



Sent using FerrariChat.com mobile app

 

Next up is check and proposition valves. The ones on the car are 30 years old. They do contain baffles springs and diaphragms. They are consumable items internally they don't last forever like a block.

"Why those look brand new Eric, how is that possible?" Mirojub and myself had a post on that topic a while back is
If anyone cares to see how you get/make a new one. Image Unavailable, Please Login

Sent using FerrariChat.com mobile app

 

On my failed pulley I don't see evidence of my belt riding high. But the walls are so thin and when you make the mistake of migging it notice how it goes all the way through the fence. At 12:00 you can see the bead on the back side of the fence went all the way through. Frankly all that did was damaged and weaken the fence making it unservicable. If it was tigged along the base that would likely be quite fine but that's not what they did on mine and not what I've seen most other people do. As mentioned previously just flat wrong on many levels.



Image Unavailable, Please Login Image Unavailable, Please Login



By the way those 4 nasty water pump bolts at the top of the block, 2 of them are NLA but you can get them in the correct spec from McMaster-carr.

Sent using FerrariChat.com mobile app

 

Mirojub, on your idler pulley in front of bank number 8 did you have a spacer between the pulley and the housing that it's pressed in? If not it would apply backward pressure on the belt and cause it to push forward just like uneven pressure on a belt sander.

I ask because whoever did my service last did not put that spacer back it's about 3 mm thick as far as I can tell I'm not exactly sure how thick it is.

Sent using FerrariChat.com mobile app

 

The new pully has a fence 2x as thick. It is far far better. However it needs s spacer as the rear snout is shorter due to a change in the engine front to beef up a bearing housing making it thicker requiring a shorter pully snout. Hence the spacer for the pully on pre Spider US models or there bouts.

 

Decided I would find TDC and mark it while I wait. Decided to use the piston stop method. The piston sticks up above the block at full stroke btw. Given that you can using a plate across the piston bolted down to the studs.

I used piston #1 which is the closest to the fire wall on the US passenger side. Turn till the piston stops, zero degree wheel to 0, then back it up (2 methods to do that) and wait until the piston hits the plate. That gives you an offset degree from the first stop which was at degreed at 0. This is essentially the 2 sides of the piston/crank dwell. If you take the offset and divide by 2 you have the true TDC.

After doing it a few times to perfect the technique of not loosening the degree wheel nut, I got 4 consecutive readings of a hair under 15 degree difference with my particular stop point as it does vary based on your stop depth there is no right number here. I turned the crank to 7 degrees from 0. I removed the degree wheel to mark the snout and noticed something interesting.... I figured I made a mistake so the wheel went back on and I did it again 2 times and got 15, then turned the motor 7 degrees from 0. Removed the degree wheel and there it was again.

My crank keyway lines up to a key slot in the bearing race. So true TDC is already set at the factory. At least on my motor. Never seen this mentioned out here before with all the posts on cam degreeing and finding TDC and setting cam timing etc. No way this "just" happened to be installed with the race slot and the crank keyway at true TDC smack in the center of the piston dwell accidently.