Strange Engine noise

[eacmen]

Hes saying he can fix the cam lobe, is this possible? Obviously he's trying to get out of paying me for a new one.

How exactly does he plan to fix the cam lobe?!? I would not let him do that. Either he is going to shim it up beyond spec or going to weld up the cam lobe which seems shady AF.

You need new cam and at least one rocker imo.

[heinzboehmer]

You can regrind the same profile into the cam, just shrunken down a bit. Then add a bigger shim to get the clearance (and hence lift), back into spec.

I've also seen people weld more material onto a lobe and then regrind it.

Both of these methods can (and likely will) kill the harness of the cam, so the person doing the work needs to know what they're doing, otherwise your newly "fixed" lobe will wear like crazy. Not sure I'd opt for either of these approaches when you can buy a new cam.

[sapote]

He might try to weld the lobe higher and then grind it down to spec, but this is not the practice being used. Ask me who else doing this? Welded cam lobe will fail again in no time.

[maupineda]

Get new cams, you are already into an expensive situation, so do it right.

cams ABSOLUTELY need to be at least 60 Rockwell C hardness, more so on an engine with “solid” lifters. Clearly those cams were not treated correctly.

[sapote]

You can regrind the same profile into the cam, just shrunken down a bit. Then add a bigger shim to get the clearance (and hence lift), back into spec.

.

Add a thicker shim won't work as it will hit the other side 180* opposite of the lobe and the valve cannot close.

[heinzboehmer]

Add a thicker shim won't work as it will hit the other side 180* opposite of the lobe and the valve cannot close.

Yes correct, that's why you grind down the entire profile, not just the lobe. Like this:

[BMWfanz]

How actually wrong installation of springs can cause cam lobe damage? If compare stock to Supertech ones- supertech are harder than stock ones and as i remember- do not have difference how to install (without markers).

[Slideways]

When you moved the DLC rocker arms, were they put back in the same position for each cylinder that they were on the previous engine? Getting them mixed up could cause this wear.

While the spring being upside down is quite the mistake, the document posted above says that the only downside to this is the spring could break.

[x Spades x]

When you moved the DLC rocker arms, were they put back in the same position for each cylinder that they were on the previous engine? Getting them mixed up could cause this wear.

While the spring being upside down is quite the mistake, the document posted above says that the only downside to this is the spring could break.

Mo, everything was laid out and put back into the replacement engine matching it's lobe. All of the other lones look perfect... just the ones they touched (valve, springs).

[x Spades x]

How actually wrong installation of springs can cause cam lobe damage? If compare stock to Supertech ones- supertech are harder than stock ones and as i remember- do not have difference how to install (without markers).

This is the info I need everyone, so I can go in there with an air tight argument. If links can be added to your response, that would be great.

He mentioned welding mor material, then regrinding down to be perfect. I didn't even want to have that convo with him at that time, until I brought him the head to point out the error. That's why I need an argument as to why the upside-down spring caused the damage. Hes saying the spring rate is the spring rate and it doesnt matter. Then sometbing about the machine pressing the spring to the exact spec, blah, blah.

[x Spades x]

Finally the issue in getting a new cam is that I need to get new DLC followers, which that shop probably won't pay for. They would cover the cam and the one rocker.

[sapote]

How actually wrong installation of springs can cause cam lobe damage? If compare stock to Supertech ones- supertech are harder than stock ones and as i remember- do not have difference how to install (without markers).

See post Thank you, heres to a fresh start!
with the smaller end under the valve keeper it doesn’t fit perfectly causing the spring to be compressed more, and the inner spring might even bind to the valve stem, causing higher load for the lobe to move.

[x Spades x]

See post Thank you, heres to a fresh start!
with the smaller end under the valve keeper it doesn’t fit perfectly causing the spring to be compressed more, and the inner spring might even bind to the valve stem, causing higher load for the lobe to move.

I checked this thread, but don't see anything referring to cams. Is this the correct link?

[sapote]

See post Thank you, heres to a fresh start!
with the smaller end under the valve keeper it doesn’t fit perfectly causing the spring to be compressed more, and the inner spring might even bind to the valve stem, causing higher load for the lobe to move.

I meant to write " See post 41 ( # and 41 actually) but somehow the text was transformed to 'Thank you, heres to a fresh start!' . It must be that the forum app doesn't like # and a number somehow.