Cam/Lifter failures in relation to oil level

[Musky Mike]

I did the filter relocation on 14 Ram 1500 and fully warmed up at idle it sits at 46-48 PSI using 5w30 Redline or PUP with an RP filter.

Mine (1000 miles) idles at 33 psi hot. A good case study would be the cam/lifter reliable rate on Hemi police cars, I would think their idle hours would be higher than their non-idle hours.

 

[GIJoe2010]

Good thought in theory, however, the Police Packages use a MOPAR oil cooler so the study would be skewed.

 

[Tach_tech]

The newer trucks all have oil coolers on them now as well. Was weather 16/17 that they added them.

 

[GIJoe2010]

It would be like comparing Honeycrisp Apples to Granny Smith Apples. They're still 5.7 Hemi's, but one's for a truck and the other a car, so there might still be discrepancies.

 

[Silver Goose]

I have taken quite an interest in the Hemi Cam/Lifter scenario. If the answer was as easy as lube pressure that can be corrected very quickly by the use of directed oil spray nozzles. Many engines use the oil spray nozzles on the back side of pistons to cool them as well as OHC engines for their cam/followers.

In my opinion, the problem could be as easy as misalignment of the cam lobe/ roller lifter. It is my understanding that the roller lifter is aligned to the cam lobe face via plastic guide device. I have used roller lifters on a few engines I have built and they all use positive metal alignment devices. The area has a lot of oil in that the lifters are pressurized to maintain proper valve lash, the crank is throwing oil in all directions along with the action of the cam lobes.

After talking with aftermarket engine builders the statement keeps coming back about the lifter roller skidding on the cam face. The cam face is locked into place so the only other player is the roller lifter. The lifter must be able to move in order to operate. Any movement that would throw the roller face out of alignment to the cam face could lead to enough movement to allow the roller to skid. Then it is like a snowball rolling downhill in that any movement from perpendicular to the cam face will cause some amount of skid. That movement which is governed by the plastic guide can over time become extreme. As stated the cam and roller are hardened, but that hardened area is only so thick.

Just my thoughts on the matter.

Larry

 

[dstryr]

If the crankcase is down a quart of oil,combined with a low idle rpm,means there's not going to be as much oil being flung onto the cam lobe as what is needed to keep the lifter roller from seizing,and consequently taking out the lobe. Hemi's that do a lot of idling do seem to have more issues ,so maybe bringing the idle up slightly might help,but there's also lots of guys who've had cam issues on trucks that have very little idling time on them,so in regards to that fact,maybe the rear gearing comes into play more.This is all speculation,but I think these questions should be asked more,about how much oil is usually in the crankcase,and the rear gearing of the truck,along with the standard questions of what oil was used and the length of time between oil changes.

Running a quart low will not affect the amount of oil slung by the crankshaft and connecting rods. As long as the pickup is covered, the same amount of oil will be pumped through the engine and returning to the sump; there just won't be as much extra in the sump. Deep sumps, windage trays and crank scrapers are on engines including a ton of high performance engines so that high rpms do not drain the oil pan, starve the pump and drop oil pressure which leads to metal-on-metal contact; windage trays help direct the oil flow back to the pan and keep the rotating assembly from aerating the oil which also leads to low pressure, and scrapers to reduce the amount of oil hanging on the rotating assembly and robbing power.

I lost the 5.7 in my '13 RAM in August of 2017 at 112,000 miles. I did not have excessive idle time, I did change oil appropriately with good synthetic and after my ordeal with the dealership and FCA cost me $4k out of $10k+ to put in a factory new engine in it. Still peeves me.

 

[guru1ofatl]

Correct me if I'm wrong but it is my understanding that the pressurized tappet oil supply is largely responsible for roller and lobe lubrication. Some of the oil that enters the tappet is permitted to pass through to the roller as shown in the following image.

 

[Tach_tech]

Correct me if I'm wrong but it is my understanding that the pressurized tappet oil supply is largely responsible for roller and lobe lubrication. Some of the oil that enters the tappet is permitted to pass through to the roller as shown in the following image.

That is an MDS lifter shown. They have a hole in the side of them to receive oil pressure to unlock the pin for MDS activation, it’s not for lubricating. The non MDS lifters do not have that hole in the side.

We have a hemi apart in the shop getting lifters, so we looked at it. There is a passage through the block and cylinder head that goes into the rocket shaft which then goes to the rocker arm, pushrod/lifter. Can’t see inside the lifter but I would assume there is a hole to allow oil flow to the roller/cam lobe. So it looks like there is somewhat pressurized oil reaching the cam lobe, not just splash lubrication.

 

[indept]

I think he was referring to the space between the roller & the lifter body just below the spring.

The sad thing is after taking those pictures they actually used those parts in a production vehicle to save a few bucks.....

 

[Wild one]

That is an MDS lifter shown. They have a hole in the side of them to receive oil pressure to unlock the pin for MDS activation, it’s not for lubricating. The non MDS lifters do not have that hole in the side.

We have a hemi apart in the shop getting lifters, so we looked at it. There is a passage through the block and cylinder head that goes into the rocket shaft which then goes to the rocker arm, pushrod/lifter. Can’t see inside the lifter but I would assume there is a hole to allow oil flow to the roller/cam lobe. So it looks like there is somewhat pressurized oil reaching the cam lobe, not just splash lubrication.

All lifters whether flat tappet or roller do bypass some pressurized oil around the lifter body itself,as the seal between the lifter body and lifter bushing isn't tight,so there is basically a small leak that will dribble some oil past the lifter body onto the cam lobe,but it's not it's main oiling.Anything that slides up and down but has no seals or rings,has to leak somewhat,or else it won't slide,lol.

 

[huntergreen]

That’s the way it’s been forever as far as a cam in block engines are concerned, so it’s hard to say if it’s really an issue.

I get what you’re saying and its entirely plausible. I don’t have any doubts that maintenance issues are a sure way to experience the issue.

Although it seems to be extended idling is the biggest issue. So it could very well be during extended idling the amount of oil actually splashed up to the cam lobes isn’t sufficient enough to properly lube the roller portion of the lifter, causing premature failure.

Tach, what is considered excessive idling ? Thanks

 

[Coramie]

Are the cam and lifter issues covered by the maxcare warranty as long as the truck is properly maintained?

 

[Silver Goose]

That is an MDS lifter shown. They have a hole in the side of them to receive oil pressure to unlock the pin for MDS activation, it’s not for lubricating. The non MDS lifters do not have that hole in the side.

We have a hemi apart in the shop getting lifters, so we looked at it. There is a passage through the block and cylinder head that goes into the rocket shaft which then goes to the rocker arm, pushrod/lifter. Can’t see inside the lifter but I would assume there is a hole to allow oil flow to the roller/cam lobe. So it looks like there is somewhat pressurized oil reaching the cam lobe, not just splash lubrication.

Since you have a Hemi engine apart or at least access to the components, could you check for me, I am very curious as to wheater or not the roller lifter can rotate in the lifter guide. I am a strong believer that at least some of the engine failures are due to the lifter rotating enough to cause the roller wheel to skid. You are correct about the lube system for the lifters.

Thank you for looking into the lifter rotation.

Larry

 

[Tach_tech]

Tach, what is considered excessive idling ? Thanks

FCA considers 20% or more excessive.

 

[huntergreen]

FCA considers 20% or more excessive.

Thanks Tach.

 

[Tach_tech]

Since you have a Hemi engine apart or at least access to the components, could you check for me, I am very curious as to wheater or not the roller lifter can rotate in the lifter guide. I am a strong believer that at least some of the engine failures are due to the lifter rotating enough to cause the roller wheel to skid. You are correct about the lube system for the lifters.

Thank you for looking into the lifter rotation.

Larry

The only way it would rotate is if the lifter guide physically broke, which I’ve never seen or heard of happening.

 

[Tach_tech]

All lifters whether flat tappet or roller do bypass some pressurized oil around the lifter body itself,as the seal between the lifter body and lifter bushing isn't tight,so there is basically a small leak that will dribble some oil past the lifter body onto the cam lobe,but it's not it's main oiling.Anything that slides up and down but has no seals or rings,has to leak somewhat,or else it won't slide,lol.

Absolutely, I imagine it would be a fairly slight amount of oil that leaks down between the bore and lifter. The MDS lifter is a little easier to see into the bottom of the body from the roller side. There was a hole that would allow oil to go through the lifter to the roller.

 

[indept]

Are the cam and lifter issues covered by the maxcare warranty as long as the truck is properly maintained?

Yes. I have seen others in this forum that have had it covered.

 

[Silver Goose]

Tach Tech, I appreciate your input, after all, you are seeing the situation first hand.

You mentioned two points, I would like to comment on:

First, FCA is willing to accept 20% failure, to me that is very high in that some of the reports that I have read lists failures at what I would call low mileage. Knowing that nothing last forever. Would it not make economic sense for FCA to reduce the failure by 50% and reap the benefits of more customers happy with the company? I know we can not change corporate policy any more than we can change the weather, but it enough people talk maybe someone will listen.

I cam from an industry where 1 failure in a million could cause you to lose your quality rating, read as a loss in business.

Second, You state that the only way the lifter can rotate is for the guide to break and that you have not seen evidence of that. Let me ask this question, can you feel any rotational movement of the roller lifter while it is in the guide? It will only take a few degrees or for that matter, a movement of any degree will present the cam face with a roller, not in 100% alignment. Once the roller is out of alignment damage can and, in my opinion, will start the roller cam face wear.

I respect your opinion and after all, it comes down to armchair quarterbacks talking about what if.

Thank you for your in put

Larry

 

[chrisbh17]

The "more than 20% is excessive" reference is to how much IDLE time on the engine, not failure rate.

Regarding that point, i find it interesting that my normal city/highway driving has yielded about a 16% idle vs driving hours on my engine. Also noted when I first bought my truck, there were more idle hours than drive hours (I suppose normal for a truck that just gets test driven?)

So am I already at risk, even with just 8000 miles? I have MaxCare of course, but would hate to rely on that in case FCA/dealer doesnt feel like honoring it (the horror...I change my oil by myself! )