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TB42 rocker shaft

Posted: Thu Apr 13, 2006 9:16 am
by Dunc Mav
This may have been covered in a previous post - but I can't find the relavant info.

Tappet ticking. Is this usually caused by wear on;

rocker shaft
lifter
camshaft
or combination.......

280 ks - gas only - use 20-60 HPR GAS Penrite oil every 5-7ks - no oil consumption. The noise is more apparent when the engine is at operating temperature rather then initial startup. I've determined the noisy tappets by sliding a feeler gauge between the tappet and the top of the valve to reduce the tick. I then reduced the tappet clearance......still noisy.

I've heard that TB motors chew out rocker shafts. Can anybody confirm this and if so what remediation work was taken ?

Thanks in advance,
Dunc.

Posted: Thu Apr 13, 2006 10:34 am
by fnqcairns
I thought it was the diesel 4.2 that had that problem but I dont know much about the tb petrol engine.
The 3 times I needed to address this problem I replaced the lot and included a cam regrind but I could have done less but wanted it done and forgoten, I dont like spanner work much.

IMO make sure you bury that 60 summer wt oil also, there is no such thing as a gas oil, it is marketing pure and simple, 60 oil does no engine any favours and a good argument can be made that if a quality 40summer oil was used you may not be facing this problem at this time.

cheers fnq

Posted: Thu Apr 13, 2006 11:04 am
by Dunc Mav
The recommended oil viscosity for the TB is about 10-30 (going by the book).

However, the following is from penrite.com.au for HPR GAS 20-60.

"The additives selected minimise nitration of the oil which can occur with the combustion of LPG. Nitration reduces the oil life and in extreme cases can cause corrosion of bearing metal."

Is ther a better oil than penrite ?????? This oil exceeds 'taxi' oil specs for Ford and Holden.

Dunc.

Posted: Thu Apr 13, 2006 1:56 pm
by fnqcairns
Hi Dunc, Penrite is a good oil, don't get hung up on Taxi spec, there is no basis to relate to your vehicle unless your engine runs near 24/7 and may include up to 5 hours idling in up to 40deg heat with the aircon on every 24 hours.
The high summer weight relates directly to idling duty once thinned and hot with low RPM engine idling a 60wt will do an OK job of forming enough of a film/barrier over the now slowly reciprocating parts, in that the 60 has its place.

In every other area of duty for an engine 60wt is a poor choice about as poor as using a 20wt for Australian conditions but for different reasons.

The gas oil you are using is a lowly rated oil (CG-4) and was not even a competent oil in relative terms when it was introduced apart from being better than the oil spec it replaced.
With regard to any standard they are a minimum, the 60 oil you are useing needs only to exceed the minimum spec by 0.000001 to exceed the standard (marketing term and who will actually test it in the market place?).
The exceeding a CG rating (marketing term) means nothing although by definition it cannot do any worse of a job than any other CG rated oil. So this oil regardless of additive claims cannot by it's rating protect a gas engine any further than any other CG oil, marketed as a gas oil or not marketed as one!

Today the oils we have are finally becoming good oils, pushed toward us by motoring manufacturers which have been pushed by government which have been pushed by green lobbies.
Todays engines esp the diesels are much dirtier engines internally because they now need to recycle much of their waste product nitrates, sulfates etc back into themselves giving no easy escape for these contaminates like in older engines, now it is the oils job to deal with them no longer mother nature. The modern rated oils have the ability to handle these contaminates in such a way that engine condition is not severely affected, a CG oil cannot protect any engine better than a CH-4 (as a minimum) or a CI-4. Take the opportunity to dump your low spec oil.
There is now an even higher spec oil under review as even the CIs can be improved upon today. I look forward to it's advantages when it is released

Some worthy examples IMO are Dello 400, Rotella, Delvac-1 there are many more, even a penrite CH or CI?, with very few exceptions and almost irrespective of make model etc in real terms if a person is not using a Ch or CI they should be!

The subject is huge and I only know enough to keep myself clear of trouble for the future, consider using a 15w-40 CI-4 for year round protection, honestly CG is for the birds if only for the slow buildup of sludge and contaminates because of a poorer ability to clean, handle and keep contaminates in suspension. Use of low spec oils will see higher mileage engines start to have oil related problems, contaminates instead of staying in suspension will aggregate like plaque in arteries constricting every oil gallery this decreases oil flow everywhere also to the top end valve train causing the oil that makes it to the top to bake before it can drain to safety, this in turn causes more sludge buildup until the engine is completely caked in sludge-it's a given sooner or later with CG oils. run your finger around the inside of the tappet cover at the fill hole.

Just one more thing 60wt oil hot and being forced through a tight journal/bearing gap is one of the direct causes of bearing failure due to the impactand spot related heat it achieves, water is very hard if accelerated, oil when squeezed through a journal at RPM is effectively a solid- Believe it or not!!

It's much much kinder to leave 60s alone and go with a 40 in Australia and a 30 in Europe and colder climates.

Sorry so long, I have a bad habit of trying to save people who use the heavy oils and also the low grade oils. Rightly or wrongly.
I have punished most of my family and friends into changing also. not singling you out, its my problem...really :oops:

cheers fnq


cheers fnq

Posted: Thu Apr 13, 2006 2:11 pm
by bogged
Dunc Mav wrote:The recommended oil viscosity for the TB is about 10-30 (going by the book).

However, the following is from penrite.com.au for HPR GAS 20-60..
I would try the recommended oil before anything else.

Posted: Thu Apr 20, 2006 8:24 am
by Dunc Mav
Thanks FNQ, that's a great help.

Fantastic !!

I'll be using 40 grade oil straight away.

Cheers,
Dunc.

Posted: Thu Apr 20, 2006 3:23 pm
by fnqcairns
Dunc hope I helped, but if you do go for a CI-4 rated oil it will darken fast as it cleans all the crap deposited on every internal surface and suspends it.
This level of contamination will be large early in the new oils life so consider 3 or 4 fairly quick changes with a CI-4 oil when coming from a low rated oil in any engine that has seen a couple of hundred thou Ks.

Something along the line of a new filter and a 1k drain, then a 2 or 3k drain then a 5K drain and new filter then whatever your normal drains would be.

Also these oils will with time free your rings up to work as designed, sometimes this increases oil consumption for a while but they will bed again and stop using oil, compression will then rise as a result. Although no oil will completly clean ring lands.

Sometimes when a quality oil does it's job it will promote oil leaks simply by cleaning the old oils crud away that was stopping the leak from showing.

So anyway sometimes it's not all beer and skittles with the quality oils and depends in the end on your engines real mechanical condition.

Castrol sells Dello 400 15w-40 CI-4 for around $80/20L from distributers so it is a good economical choice to get the ball moving.


cheers fnq

Posted: Thu Apr 20, 2006 4:07 pm
by rOd
fnqcairns wrote:Castrol sells Dello 400 15w-40 CI-4 for around $80/20L from distributers so it is a good economical choice to get the ball moving.
Is'nt that a diesel engine oil?

Is this oil suitable for a TB42 petrol engine?

Rod

Posted: Thu Apr 20, 2006 5:18 pm
by fnqcairns
Hi Rod, yes rated as a diesel oil (designated C) the upshot is that it is a tough HD oil, in a petrol (designated S) engine this oil leaves that much more room for abuse, better quality additives and more of them etc.

The oil manufacturers don't muck about with their reputation and HD diesel oils.
I know of no instance where a highly rated C oil would not cakewalk the rating to the highest S - its a given, although for the manufacturer to bother paying the hundreds of thousands for the tests it must fit the marketing model.

Just not worthwhile to sell a high cost of manufacture quality oil to the great unwashed for a fair price when a low cost oil to manufacture oil can be marketed with great appeal instead.

If it were left up to the oil company's we would still be using a CF or it's equivalent S 1980s technology oil.

cheers fnq

Posted: Thu Apr 20, 2006 9:01 pm
by big ben
thanks fnqcairns, now i just gotta remember some of that!
I do know on nissan RB series, sr20 etc.. DONT use heavy thick oil, its the one thing that will kill em
A lot of people think THICKER THE BETTER
A mate put thick oil in his honda motorbike thinking he was doing the engine a favour, lasted a week then blew up!

Posted: Thu Apr 20, 2006 10:13 pm
by fnqcairns
Yeah Ben I buggered a few engines in the past thinking oil was oil and thicker was better. Thought it was just my bad luck at the time, now I know better and expect to see 500k or more out of my petrol 4cyl injected Mazda engine bottom end and still in spec, 400+K now and still going strong :lol: hope the body lasts :?

cheers fnq