Engine Run In Proceedure

[Terry]

Hi, 

while doing some other IT/Website work tonight I ended up on the Crane Cams Australia website and noticed a link to this page on running in a new cam in a new engine and while they mainly mention Chevs and Ford I think the general gist of the procedure applies to our little beasties as a general guide.

http://cranecams.com.au/pdfs/CAM%20RUN%20IN%20PROCEDURE.pdf 

Everyone seems to have there own ideas for how to run in an engine, this is just another view. 

Terry

[Boxhead]

Heyo Terry, back in the olden days or back in the day as the kids say there was never any mention of "Running in a cam". Running in a new or overhauled engine proceedure was to take it easy for a while and gradually increase parameters till after 100 miles or so engine was considered "Run in".
All engines were flat tappets and there wasn't any problems, now days on yotube many people say you must do a cam run in before driving car.
What's changed? Didn't we know any better? Has engine overhaul and cam metal changed?

[Terry]

Hi,

I think that some of the new thinking is from a better understanding of how things work and in the case of the followers all the cam rebuilders seem keen to tell you that they need to be dished on the bottom so that they rotate.

Another change I understand is in the oils available today have much less Zinc in them which seems to be a key ingredient in the cam lube stuff they recommend when first starting up.

Everyone has there own views about engine running in and how often to change the oil and to a greater or lesser degree I think it comes down to what has worked for them in the past and if it hasn't caused them problems they have no reason to change.

[sodamoke]

Much of the "new thinking" on the Camshaft makers websites is a result of the greater lobe lifts and therefore heavier valve springs necessary to control valve bounce at the higher rpm needed to get the benefits from larger camshafts.
All lifters should be radius ground and a decent camlube used for assembly. All Mini engines need high zinc oils

[FNQ]

Good link, thanks Terry. As stated by sodamoke , lifters should have a radius on the face.  Note (IMO) , most new lifters we source from mini suppliers DO NOT have a radius, so need a wide cone profile radius put on them. In my experience the  expensive isky style lifters available from apt-fast in the states are the only ones that are radiused and are guaranteed to be suitably hard.( again happy to be corrected)



Cam specialists and old school machine shops are the places to go for machining  all others, ( thats right,  brand new parts that needs fettling before fit for use) however it is a fiddly job to correct the faces of 8 tiny little cylinders , so workshop time is a bit more than expected.


Also note the cam lobes themselves , were initially designed with 'run out'( for want of a better descriptor), so a gradient edge on the lobe and the radius lifter top all contributed to helping the lifters turn in the bore.  ( now goes off to put flame suit on !!!)


Even now i don't like idling for extended periods of time without blipping the throttle- i just 'think' (ie no real evidence) that the tappets will rotate better at around 2 thousand rpm Cheers Darryl

[mokebloke]

We had the Moke engine (A+ Mini Metro block) bored and new bearings throughout mebe 12 years ago. There was no mention of "Running in camshaft" by either the builder or the engine shop that did the machining, we just went easy on it for a while giving it a burst every now and again. Kept clean oil (GTX Ronnie recommended) up and did a change at 1000 K's then again at 3000. That engine is still humming nicely with about 30,000K's, seems no noticeable drop in performance. With all the doomsday talk of not correctly running in a cam can I expect the engine to explode shortly?

[FNQ]

in response to mokebloke's shrewd take on this ( and to anyone else who can put up with my ramblings)


I am pretty sure you can count on continued good service life for a well put together and well maintained motor, ( if you want to worry , worry about drop bears instead!!!)  .


My take on all the 'world is coming to an end' worry about cams and ZDDP is that:-
  there was a period when the oil changed mainly due to tighter euro standards
  there was also a necessitated change in the processes used for case hardening ( nitriding and the like)
  flat tappet camshafts engines  were becoming more and more relegated to'small potato status' and relics for most of the motor industry         trade and by and large didn't care what was happening to pushrod engines
  CAM manufacturers heard about failures_ labelled as  dodgy cams ( mostly on high rpm muscle car type builds)


Somewhere in the confluence of those things , there were cases of excessive wear on cam lobes.  Crane cams and other big companies suddenly woke up to the changes and stipulated a slightly more rigorous run in procedure.


So BMC motors have always enjoyed relatively high levels of ZDDP, and apparently the newer additive packs that use other chemicals to either reduce friction or create  oil film barriers etc don't quite cut if for our motors, but many engines can handle the changed products well ( sharing the gearbox with engine oil has some failings)  ( case in point Castrol EDGE semi synthetic was a good oil for our engines and one of the slipperiest and cleanest running oils for that viscosity rating i have seen.... in some instances i couldn't clean the oil feel off parts that i wanted to strip,,,, but when they (Castrol) went Titanium Edge the blend was not as good for our particular engines


Having said all that , for engines that putter around under 4000 rpm for all their life , that have mildish road cams with appropriate less steep ramps, any old oil and any reasonable run in procedure  would probably do just as well as lots of new fangled stuff.

[mokebloke]

Heyo FNQ, I have bin doen a bit of light reading on oils lately. What's your take on fully synthetic or blended oil? I know they say it's has good quailities but..........I tried a full synthetic in a Honda motorcycle I have and it seeped out every gasket. Also tried a semi synthetic in a petrol Mitsubishi Triton, same result. Back onto full mineral oil now with high content zinc if I can find it. When I use all the 5 litre containers I have in the shed I might splurge on a 200 litre drum, mebe Penrite. All our engines are older stuff as well as a few V8's so a good mineral oil will do me nicely.
Sorry to hyjack thread Terry 

[FNQ]

good quality mineral based oil is excellent mokebloke. As a rule i try and stay within one or two SAE specifications on the OEM stipulated oil.


So if a 76 torana came out with an SG rated oil , then i might go SJ or similar just to find a grade that is still being produced. Later cars ( say after 2000) i actually have to read the euro ratings rather than SAE,, to find out whether B3 B4 can be superceded by C3 ( just an example). In these vehicles the base oil quality is the driver, whether they be mineral semi or full synthetic.  I have run slightly altered viscosity ratings in these oils. So instead of 20W 50 i run 15 / 40 etc.   Most oil makers show ZDDP content in their product sheets, but some a very hard to find. I like the Penrite products, and am currently using in a euro VAN, a nissan xtrail diesel, my road mini , a mazda c5 , nissan micra and a 71 torana and two motorbikes. ( these are not all mine, but rather mine. wife, daughters (plural) - guess who gets to buy all the oil and do the changes?? ) Sadly they mostly take different oils so i just buy  20 litre drums when on special. So long as you change regularly i think most oils are okay. I used to use repco 6 litre stuff in a road mini, but found penrite or valvoline classic equally good.  If you believe the results of used oil analysis ( such as done in commercial fleets, but sadly still a bit too expensive for me in australia , we mostly err on the side of overchanging out oil when we do regular kilometres, ( so the oil additive pack is still good  at 15000 km but we change at 10 000). BUT unless you track it, it is better to pay $100 more per year on oil and a filter, rather than thousands on a premature rebuild)




Another hot topic ( we have already run the gauntlet of   what engine run in procedure and  what oil to use) for sometimes heated debate is that of oil filters. - and if you thought finding out info about oil was difficult try getting consistent info from filter makers...  but again moving way off topic