Cam oiling ?

[jsawduste]

Perhaps I missed it but why all the interest in additional cam oiling ?

Seems that if a good oil is used and valve spring pressures are kept resonable the stock set up works fine. What am I missing here ?

[gradon]

It's because people around here have this problem with thinking out of the box and can't stop tinkering with their Jeeps.

[jsawduste]

It's because people around here have this problem with thinking out of the box and can't stop tinkering with their Jeeps.

All right, I respect that that.

[Mgardiner1]

There were a number of Crane cams that failed in these engines, and people have measured the stock cam lobs on high mileage engines and said they were out of spec. Of course nobody wants to build a performance engine and EXPECT to only get 10k miles out of it before considering changing a camshaft. I don't frown on anybodies idea for the extra oiling. It kinda makes me feel like maybe i didn't think about it enough.... but high zddp oil and OEM mopar cam are hopefully going to be my savior....

[jsawduste]

There were a number of Crane cams that failed in these engines, and people have measured the stock cam lobs on high mileage engines and said they were out of spec. Of course nobody wants to build a performance engine and EXPECT to only get 10k miles out of it before considering changing a camshaft. I don't frown on anybodies idea for the extra oiling. It kinda makes me feel like maybe i didn't think about it enough.... but high zddp oil and OEM mopar cam are hopefully going to be my savior....

Some random thoughts on the issue;
1. Most of us would agree the 4.x engine family is a proven,long lasting, durable design.
2. Most of us are still spinning the engines within the factory 5200 red line.
3. If I recall, many of the cam failures (not just Jeep 4.0`s) was in a time frame that had reductions in ZDDP and not a lot of knowledge was out there for folks to know.
4. About this time there was a flood of import lifters that were sub standard in design and manufacture.
5.Wonder how many cams died that were sold as a kit (cam and lifters) from an aftermarket supplier ?
6. Increasing the amount of oil is not really going to do anything. You can only build so much surface film given the parameters the engine see`s. The durability of the 4.x engine has not been questioned, has it ?
7. The key is to have an oil that has the required properties to maintain the integrity of the surface film. Warm beer doesn't taste good. More warm beer still doesn't taste good. Now take that warm beer and chill it. Then we have something we like. Same thing with oil. Give the engine the oil it was designed to run with.

[SilverXJ]

6. Increasing the amount of oil is not really going to do anything. You can only build so much surface film given the parameters the engine see`s. The durability of the 4.x engine has not been questioned, has it ?

I have seen a few stock 4.0l cams with damage. One was the original one in my 2000, one was from a 2004, one was from a 2000 block.

[jsawduste]

6. Increasing the amount of oil is not really going to do anything. You can only build so much surface film given the parameters the engine see`s. The durability of the 4.x engine has not been questioned, has it ?

I have seen a few stock 4.0l cams with damage. One was the original one in my 2000, one was from a 2004, one was from a 2000 block.

OK, but were the engines fed an appropriate ZDDP oil ?

ZDDP levels began to fall around this time. With the advent of goverment, industry and technological changes.

[SilverXJ]

OK, but were the engines fed an appropriate ZDDP oil ?

ZDDP levels began to fall around this time. With the advent of goverment, industry and technological changes.

I don't recall what oil I used in my original engine, but I think that the other probably used what ever oil was available. I don't think that the 4.0L with a stock cam should require special oil.

[jsawduste]

OK, but were the engines fed an appropriate ZDDP oil ?

ZDDP levels began to fall around this time. With the advent of goverment, industry and technological changes.

I don't recall what oil I used in my original engine, but I think that the other probably used what ever oil was available. I don't think that the 4.0L with a stock cam should require special oil.

Nor did the SBC/BBC etc. guys when they used New-Old cams with the new oils. Seems they were wiping lobes on parts that had been proven to work together for years. Came down to a lack of understanding the changes in oil formulations.

[mohawk225]

Some time in the past cleveite decided the rod bearings did not need the cam oiling squirt hole in the bearing... my Napa man called cleveite and verified this because i told napa they had the wrong bearing since it did not match mine.
cleveite said they decided it was not necessary..... i wonder if this may be part of the problem with people having cam problems after building engines... and maybe factory.... i have only pulled 3 engines apart and have always found the hole in bearing... and no cam problems... knock on wood....