Beretta.net

93 quad 4. So my idle had been rough for probably a month and would miss fire while driving like once a week. One day on way home from work, the car started smoking, from oil coming out of the cam tower cap. Got it home looked at it and there is a big crack driver side corner exhaust tower cap. pulled the cap off, (not sure of technical name for it) but the disk where the cam hits broke in half and i am guessing cause the crack. My question is can I try to just replace the cam tower or the whole head. Sad part is even with the crack the motor runs great while driving.

Misfire fixed?

When the father in law moved it the other day(storing it as his place) he said it ran really smooth. Just trying to figure out if I can replace the part that broke and weld the crack, or if I should just replace the whole tower or get a new head.

Replace the cracked cam tower. Just be sure to use a HO cam tower

1988GTU wrote:Replace the cracked cam tower. Just be sure to use a HO cam tower

Cam tower = cam housing, right? I don't recall that the H.O. housing was any different than the L.O. (Normal) Quad cam housing. The cam is different, yes, and I don't know that it would be a good idea to replace just the upper half of the cam housing (it would kind of be like mixing 1/2 new rod bearings with 1/2 old bearings -you replace them only in matched halves), but there should be no need to replace the head if it isn't damaged. You will have to open the timing-case to unbolt the cam housing from the rear of the case, but you would need to do that anyway to unbolt the sprocket, re-time the chain, and re-set the tensioner...

Cam tower to me is the whole cam carrier assembly/housing.

LO vrs HO = smooth vrs non smooth style.

= LO

= HO

I don't think there is actually a difference in any of the casting style/quality or more importantly, specifications between L.O., H.O., or even W41 housing/carrier/tower/whatever. There may be a finish-quality difference from one year to another, I don't think so though. Mostly, I think you are seeing the difference between old/corroded and clean/well-taken-care-of engines. So far as I recall, the only functionality difference in the cam housings was on the SOHC engines (which never made it into a Beretta), as they switched mid-year '92 from using the intake cam housing from the DOHC engines to using the exhaust cam housing (or vice-verse).

Please relook at the pictures.

You cannot run all cams and lifters in the LO version.

Okay, I see the difference you are talking about now. I still think that is a year-group difference, not a VIN A/VIN D distinction, as it looks like they changed the casting style for the '90 year, but I am not certain. However, the lifters DO cross-reference for all Quads from '87 up except for the '95s, which appear to be using the 2.4 Twin Cam lifters instead, so I am still not convinced that the housing would not be interchangeable. But, I am not a Quad expert, and have only had a few engines in that family, and most of those were the 2.4L cousins. I guess further research would be necessary, unless a Quad expert wants to chime in here to settle it for us.

It's hit or miss with HO cams in the LO towers, but more likely be an addressable concern with cams that contain more lift.

To be safe for those that swap and go parts, it would be in ones best interest to stay pure with guarantee to interchange parts.

1988GTU wrote:To be safe for those that swap and go parts, it would be in ones best interest to stay pure with guarantee to interchange parts.

Yeah, I would overall agree, and would go that route myself generally speaking, but it may be harded to find parts specifically sourced from the rarer H.O engines, and I think the cam housings are actually the same part #, casting, etc. between the 'A's and the 'D's (again, I could be wrong ), so NOT getting a new housing vs getting a VIN D housing, go for the L.O. if there isn't an alternative, especially in a case like this where the original has actually cracked.

Yep.
The yards over here tend to have the intricate towers all around. As a whole though, quad 4 2.3 parts in good condition is becoming a thing of the past.

I'm not really sure how the 2.4 cams compare to the 2.3 H.O., although I should research that just for myself. But the 2.4 Twin Cams have a direct-drive P/S pump that makes the Quad's belt-driven POS look like, well, a POS. Depending on what the bigger engine's cam profiles look like, that would be a nice little upgrade, and the 2.4s are a lot easier to come by these days. Pretty sure you would lose some performance though...