57 replies to this topic

[CPC]

I just wondered if anybody has had this before..

 

This is from my 2000 mile old 1380 engine

 

I also have wear on my swiftune cam aswell..

 

what caused this, its been mentioned poor quality cam followers?

 

Chris.

 

[Wim Fournier]

Or, it is caused by bad oiling.

Are all oil canals in the block free. is the oil pump in good order. Do you use an oil filter with a valve to avoid all the oil is running out of the block into the sump when the engine is at rest. Is the valve and spring that controls the oil pressure in good order and is the sitting for the valve not obstructed?

What oil dit you use when you build up the engine? There is special lubrication needed for the first turns that the cam shaft makes when starting up the first time.

[imaparana]

I had the same thing with mine, after more miles but again with a swiftune cam

[CPC]

I did not build the engine, it had 500 miles on it when I bought it but by 2000 miles the head gasket had gone/ gearbox stripped teeth and this!

[miniQ]

Pull the camshaft and put some pictures of the lobe surfaces up.

[mini-geek]

I had this on an MED cam similar use..

[sledgehammer]

what state was the oil in ?

 

how much metal on sump plug ?

 

wrong oil ?

[Magneto]

As Wm Fournier mentioned, what oil did you use? Flat tappets cams like these need oil with a lot of zinc in it ....

[slidehammer]

Don't like to say this I would question the quality of the engine build in the first place, as you have had an awful lot of issues for what is supposedly a low mileage engine. I would suspect poor original build or first start / run in procedures on the first 500 miles I would pull the lot apart and re-assemble check it over.

[Orange-Phantom]

Exactly the same thing with me!

 

4000 miles, Car built by Miniworld and Peter Vickers supposedly one of the best engine builders in the UK for A Series.  I wasn't impressed when my brother and I stripped the engine down.  The followers and the Cam was shot, was meant to be a SW10 cam but in fact was a reground Kent 276.  Explains some of the quirks with the engine.  The cam springs used were far far far too strong!  Two hands required on the spring compressor!

 

I've got new cam followers from Kent (I wouldn't use anything else) new Swiftune Billet SW10 cam which is crossdrilled to supply oil directly to the followers, new springs that match the cam from Swiftune, (Only one hand required to operate the spring compressor which tells me alot) new cam chain, new oil pump (Oh and new clutch plate, clutch release bearing head gasket etc!!!)

 

Whoever put the gearbox together needed a good talking to also!  The reverse idler gear was shot, it bent the selector fork and the pin was worn too.  It wasn't shimmed up properly and they machined the gear down on the engagement side which butchered it properly.  Thankfully everything else in the gearbox and engine is like new.

 

It's now all back together properly, the cam is timed in properly instead of at 114 degrees!  (So called professionals my backside)!

 

Check your valve springs rates too and if you get new cam followers I'd recommend the Kent Cam Followers.

 

I've been using oil designed for the Mini with the optimum level of Zddp so I know it wasn't the oil, maybe when it was setup on the dyno but I suspect it's the valve springs which were far too strong causing excessive wear.  When running in an extra dose of Zddp doesn't do any harm for running in your cam (don't go above 2000ppm as that then can cause cam galling) and then drop the oil when run in for some fresh stuff.

 

I'm nearly there and can't wait to have it back on the road.  It'll be like a new car!  I only wanted to change the final drive!  I'm very glad I pulled it apart now!

[CPC]

I only found this fault by luck and yes I'm in the process of a complete rebuild.

I had been using valvoline VR1 oil that I'm led to believe its the best and the sump bung was fairly bad with a few teeth from 1st synchro attached!!.

I will post a pic of my cam.. I have gone over the pitting with 1200 grit wet and dry lightly so may have ruined it?? It looks better but still some pitting and guess it needs to be measured..

The oil pressure relief cup part had heavy scoring as well. I was running a oil pressure guage and cold first start idle and under load was around 75psi and around 25psi at hot idle

Edited by CPC, 05 September 2016 - 05:56 PM.

[tiger99]

I presume the followers were renewed with the cam? You probably know that, but for the benefit of others, especially those new to the car maintenance scene whom we wish to encourage, it cannot be said too often that you never, ever run new followers on an old cam or vice versa. The reason is quite simple, the old item has been work hardened and will chew up the soft new one. The highest working pressure in the engine is the line contact between cam and follower. That is a reason for needing special cam lubricant during assembly, as recommended by the cam manufacturer.

[Orange-Phantom]

If the cam has pitting in it then I'd be replacing the cam, it sounds shot to me. What are the lobes like? Sanding down a cam sounds like a recipe for disaster.
If it's pitted and your going past that your losing all the surface hardening so you're going to have even more trouble sooner rather than later. That's why I stated about the Kent cam followers, I'd assumed you were going to replace the cam too. I would!

Edited by Orange-Phantom, 05 September 2016 - 06:32 PM.

[Spider]

A few things I see there.

 

The Cam follow wasn't spinning. This could be that it was tight in the Block or the Cam and / or the follower wasn't Ground correctly.

 

The Cam Lobes should not be parallel to the Cam Centreline but have a very small taper on them, all of them should be ground the same way with the 'small' side being on the Pump End of the Cam. I've said it before and it irks me to do so, but I haven't seen a properly Ground Cam from the UK in many years, though I must say, I haven't looked at them all.

 

The - so called - Flat Face Cam Followers have to have a Radius Ground on the face, typically on a 36 to 42" radius. This can be checked to a small degree by putting the Follower on a ground flat surface and rocking it over and trying to get a 0.0015 to 0.0025" feeler gauge under the other side. This is not a conclusive test, but shows you are on the right path.

 

The other problem I see is I don't think there wasn't any or the right type of Cam Lube applied at the time of the build, or it ran off before it was started. It may have had the Lube applied, but the Cam wasn't run in following it's first start, but this point leads in to my next.

 

Last thing I see is that the cam Follower is poor quality. Even given all the points above, which I am sure would have occurred in any case, just that this showed up early. The Grade of Iron that may use these days is poor (has a lot of contaminates) and many are not surface hardened.

 

There's presently only two followers that I use these days, those from APT in the US and also those from Isky, but these too I buy direct from the US as I was sold some from the UK that were not the same as those I get from Isky themselves.

[Spider]

Some measurements showing the Taper in the Cam lobe (and before anyone says, yes, the vernier isn't the best for the job here, but is good enough to be able to identify what's going on);-