Question for people who have wiped a cam out

[Nick Micale]

Actually, it is my opinion that it not only expedited the problem, but was the source of it.

Having done hundreds of new cams in original and rebuilt turbo V-6's engines, we have only had 2 flat tappet cam failures. Both were because the owners insisted on using Mobil I against our advise.

One lasted 25K miles, the other less than 10K.

For 20+ years I have stated that this "60's technology and design" engine should be run on regular oil [with EOS if modified] and not synthetic.

I know some racers that use synthetic with EOS or similar additive, but it is changed after each track outing. Yes, it is expensive, but so are their engines.

Thanks for your reply.

 

[Nick Micale]

was using Mobil 1 synthetic in mine when #3 went....had 36k on rebuild....also popped head gasket on #3....kinda think it was related...but who knows...had also just installed an alky control kit...so it could have a been a combination of things

Again, my opinion, but I do not see any relationship to a blown head gasket and a wiped cam?

I base this on having replaced MANY heads gaskets for local owners. The "king of blown head gaskets" had over 10 replaced on his GN and never had a cam problem.:biggrin:

 

[Razor]

A wiped out cam can lead to improper cylinder pressure=blown HG

Wipe out the exhuast lobe.. the pressure has no where to go.. make sense?

I too agree with the regular oil.. a call to Reed cams is Ga a few years ago said the problem with synthetic oil was it was too slippery.. and the lifters have to spin in the bore as the cam goes around. If you put oil that is too slippery, the lifter stalls.. and then wipes itslef and the cam.

As to blown headgaskets.. they happen when racing.. there are ways to minimize the risks.. but there is always a risk when racing an engine. More so when someone beats on the engine on a constant basis..

 

[John Wilde]

My car would show high KR on the scan master. I would get like 19.5 and would always happen around 7 psi and up. Also the car had no power at all. Could not even spin the tires in the burn out box.

I was getting a whole bunch of what I thought was false knock.
Unfortunately there was a lot of slop from the lobe being almost totally dead.

 

[ACLR8R]

Just FYI, I was using Amoil full synthetic when my cam went, it had about 25-30k on it. Now running Rotella with EOS.

 

[gbsean]

one thing I do know for sure is Mobil 1 synthetic and water do not mix....which is why I had to do entire motor....the builder of Engine who is well known told me to use Mobil 1....my new Engine builder told me to use regular dino oil...and as this one has a roller setup it should be fine......

on a side note...the knock detector was going nutz thru different RPM ranges but DS was not showing any timing retard....it wasn't until pulled the intake that I could see the head had lifted...and #3 was wiped.....also #1 was also starting to show sign of wear....

 

[TA49-WE4]

Inquiring minds would like to know what type and brand of oil you were using, thanks.

Mobil 1 is the oil I had been running in the engine. I just switched over to castrol regular oil with zddp added to it, but I think the damage had all ready be done before the zddp was even in the engine.

 

[84BuickGNYorkPA]

Now running Rotella with EOS.

+ 1 Rotella and 1/2 bottle of EOS

Chuck

 

[84BuickGNYorkPA]

Actually, it is my opinion that it not only expedited the problem, but was the source of it.

Having done hundreds of new cams in original and rebuilt turbo V-6's engines, we have only had 2 flat tappet cam failures. Both were because the owners insisted on using Mobil I against our advise.

One lasted 25K miles, the other less than 10K.

For 20+ years I have stated that this "60's technology and design" engine should be run on regular oil [with EOS if modified] and not synthetic.

I know some racers that use synthetic with EOS or similar additive, but it is changed after each track outing. Yes, it is expensive, but so are their engines.

Thanks for your reply.

Nick,

Thanks for sharing your exsperience, very powerful information right there. I'm on the fence on my new built motor for a roller cam.... hard to justify all the money these cars eat up...

Chuck

 

[GNRick]

I bought my 86 GN last August. Mileage was just under 25,000 miles. Original owner told me that her husband only used Mobile 1 synthetic. So when I got it home, I changed the oil and put in Royal Purple with a bottle of ZDDP. Now after reading this I want to run out and put in Valvoline racing oil and another bottle of ZDDP.

 

[blackbox]

How is syn. oil with a roller cam?

 

[A2000RICH]

I bought my 86 GN last August. Mileage was just under 25,000 miles. Original owner told me that her husband only used Mobile 1 synthetic. So when I got it home, I changed the oil and put in Royal Purple with a bottle of ZDDP. Now after reading this I want to run out and put in Valvoline racing oil and another bottle of ZDDP.

GN rick---------like all good things there can always be too much of a good thing-------while there is plenty of solid evidence that supports the function of adequate amounts of ZDDP in oil there is also credible evidence that too much can have negative effects------without going into the details the optimum amount in a high performance engine is in the 1800 to 2000 PPM--------more or less is equally not good-------you wouldn't want to add much if any to valvoline racine oil----------1/2 bottle of EOS or 1/4 bottle of ZDDPlus would be right at the limit.............RC

 

[GNRick]

GN rick---------like all good things there can always be too much of a good thing-------while there is plenty of solid evidence that supports the function of adequate amounts of ZDDP in oil there is also credible evidence that too much can have negative effects------without going into the details the optimum amount in a high performance engine is in the 1800 to 2000 PPM--------more or less is equally not good-------you wouldn't want to add much if any to valvoline racine oil----------1/2 bottle of EOS or 1/4 bottle of ZDDPlus would be right at the limit.............RC

Richard- I'm referring to the VR-1 Racing Oil that is street friendly, not the all out racing oil that is short on detergents. How did Royal Purple do in your testing? Would you also agree that Synthetic oil is bad for our cars?

 

[Nick Micale]

How is syn. oil with a roller cam?

One other problem with synthetic oil, as compared to regular oil, is that it will not stay on bearings and cylinder walls, it will "drain" off after a couple days.

Roller cams have extremely high pressures on the small needle bearings and MUST have proper lubrication for decent life. The solid rollers with very high spring pressures can be "life threatening" to the roller bearings as well as the cam itself without good lubrication.

Cylinder walls also need to have good lubrication especially at higher RPM's. Even though synthetic oil has a slightly higher flash point, I prefer the "staying power" of regular oil. Yes, we have seen roller cam failures in various make engines, as well as a few Buicks.

A 8-900 HP race engine is a much different animal than a street-driven 300 HP engine. When dis-assembling one of our engines using Valvoline and an additive, a slippery film is on everything and will not even wipe off. This is not the case with synthetic oil.

 

[FattyMcTrickle]

So Mobile 1 is no good eh, thats nice to know now..... Good thing its only been one oil change. What is EOS or ZDDP??

 

[turbojd]

It's an oil additive with phosphorus and zinc, which most of todays oils have lowered amounts of, for flat tappet engines.

 

[84BuickGNYorkPA]

So Mobile 1 is no good eh, thats nice to know now..... Good thing its only been one oil change. What is EOS or ZDDP??

http://www.turbobuick.com/forums/ge...76-gm-engine-oil-supplement-eos-question.html

ZDDPlus™ - ZDDP Additive for Classic Cars - Agricultural Equipment

 

[A2000RICH]

One other problem with synthetic oil, as compared to regular oil, is that it will not stay on bearings and cylinder walls, it will "drain" off after a couple days.

Roller cams have extremely high pressures on the small needle bearings and MUST have proper lubrication for decent life. The solid rollers with very high spring pressures can be "life threatening" to the roller bearings as well as the cam itself without good lubrication.

Cylinder walls also need to have good lubrication especially at higher RPM's. Even though synthetic oil has a slightly higher flash point, I prefer the "staying power" of regular oil. Yes, we have seen roller cam failures in various make engines, as well as a few Buicks.

A 8-900 HP race engine is a much different animal than a street-driven 300 HP engine. When dis-assembling one of our engines using Valvoline and an additive, a slippery film is on everything and will not even wipe off. This is not the case with synthetic oil.

nick------interesting comments------and actually the subject of adhesion relating to oils and surfaces is extremely complex and is way beyond just a synthetic vs mineral oil issue------since starting ZPlus we have spent a silly amount of time and money researching and testing oil characteristics-------much of what we have learned or put together has resulted in a series of tech briefs on our web site------and yes there has been in the works for a while tech paper #11 that is dedicated to just this subject------your comments have prompted us to put it on the front "burner"-------i hope to have a preliminary version out VERY soon-------and i promise it to be interesting and factual....................RC

 

[Nick Micale]

Will be very interested is your results when ready, always open to new and better information and products.

My info on the synthetic "drain down" was from a couple GN engineers I meet at a conference years ago. They actually worked at the GM in the engine development group.

Their testing showed the potential for dry starts if the engine would sit for a few days. Do not know if they published any of their results or not?