Oil & Flat Tappet Cams

GT2 · 11-01-2013, 10:45 AM

My understanding is that modern engine oils no longer contain zinc which is required for the longevity of flat tappet cams and lifters as used in older vehicles. Has anyone else heard of this?

I was reading recently that in the USA, they get around this by using oil made for diesel engines as the oil has the zinc content.

I'm interested in people thoughts and experiences?

XBROO · 11-01-2013, 11:05 AM

Don't know, I run penrite hpr 30 in my old donk, would only use mineral oil for an old V8.

The Yeti · 11-01-2013, 11:13 AM

Yea I have heard this, but the salty old guys running my type of old banger all sware byt HPR 30, so Ive been running that, mine doesnt have an oil filter so I change it every 2500km

350125GO · 11-01-2013, 11:26 AM

The Penrite I use has a little label on the bottle mentioning added Zinc...

spannerman · 11-01-2013, 01:10 PM

Yup another one for penrite hpr 30
I was running castrol until I chewed a cam up (351 clevo)
engine guys recommended it after it happened

noflac52 · 11-01-2013, 01:43 PM

Yeah its correct that the roller cam oils don't contain zinc and that you do need it for flat tappet cams.

The blokes who did the machining on my 347 windsor made a point of telling me this to protect my new cam. They also asked me to bring my new cam in to check that the lobes were machined with a three degree taper to spin the lifters correctly as they have had a number of flat tappet cams fail in the last two to three years due to inaccurate machining. When I asked them why it is happening all of a sudden with flat tappets they said that the market for flat tappet cams is now so small that they no longer have priority with the major manufacturers and sometimes quality control slips. This coupled with the incorrect oils increases the risk of failure

JimStone · 11-01-2013, 02:32 PM

Another one for HPR 30, highest content I could find on the Australian market for the viscosity I need

http://www.penriteoil.com.au/tech_pd...C%20LEVELS.pdf

http://www.penriteoil.com.au/images/...20Bulletin.pdf

http://www.penriteoil.com.au/pis_pdfs/0HPR%2030.pdf

smciner1 · 11-01-2013, 04:01 PM

I have heard of this also. A friend chewed out his Flat Tappet Cam in his XB GT because of this. He later found out about the lack of Zinc in new Oils. He ended up replacing his Cam with a Roller to avoid the issue. I did the same on my XB when I has the Engine rebuilt recently.

Apparently the removal of the Zinc was to do with emissions. Most (probably all?) new Cars run Roller Cams of some description now where the lack of Zinc isn't an issue. As someone else has stated, flat tappet Cams are such a small percentage of the market now they aren't a priority.

Some Oil available still has the Zinc in it (Penzoil do one I think) and you can also buy the Zinc Additive.

I have also heard that a lot of Cam Companies don't give a Warranty on Flat Tappet Cams now.

Is it worth moving this thread to the Worksop Area?

**gregaust** · 11-01-2013, 05:14 PM

What about lead? Was mentioned to me that zinc is one part but lead was also used as a form of lubricant and has been removed. Was a new one on me

TC200six · 11-01-2013, 06:15 PM

Quote:

Originally Posted by GT2

My understanding is that modern engine oils no longer contain zinc which is required for the longevity of flat tappet cams and lifters as used in older vehicles. Has anyone else heard of this?

All oils contain zinc. It's just that oils specified for new cars have lower levels of zinc like oils labelled as "low SAPS".

The good think about Penrite is that they label which of their products are "Full Zinc" or not. Although if you look at their latest oil summary you can see they have reduced their zinc level in HPR 30 quite a lot.
http://www.penriteoil.com.au/tech_pd...19th%20Nov.pdf

If anyone's worried, buy Classic light instead. It still has 1760 PPM

http://www.penriteoil.com.au/tech_pd...INE%20OILS.pdf

**SSD-85** · 11-01-2013, 11:20 PM

Zinc dialkyldithiophosphates more commonly known as ZDDP were the principle lubricants in older oils for flat tappet camshaft engines.

They have significantly reduced levels of ZDDP over the years due to roller cams not needing it, along with the compound damaging cat converters.

I personally used Penrite HPR50 as their datasheet indicated (as above) that levels were sufficient for most flat-tappet engines.

Pennzoil GT oil has higher levels, but is no longer distributed here. Apparently Valvoline VR-1 has sufficient levels too.

Penrite Classic Light is defeintely the most suitable, just costs one of your kidneys.

HO 3 · 12-01-2013, 09:30 PM

Quote:

Originally Posted by GT2

My understanding is that modern engine oils no longer contain zinc which is required for the longevity of flat tappet cams and lifters as used in older vehicles. Has anyone else heard of this?

I was reading recently that in the USA, they get around this by using oil made for diesel engines as the oil has the zinc content.

I'm interested in people thoughts and experiences?

Not following correct break in proceedure for flat tappet cams has probably caused as many if not more cam failures before the first 1000ks as not running an old school type oil.

Cheers Mick