54 replies to this topic

[Dusky]

The machine shop are the ones who installed the main crank, conrods, and fitted the pistons to the block. So i figured they new what they were doing because thats all they specialize in. Compression ratio i believe is 10.1

Right now i dont know what castin it is but i would assume its the normal one.

What do you mean by chamber enlarging?

Thanks for the reply

The combustion chambers need significant enlarging to get you at a 10:1 ratio if you 'd use flat top pistons.
I wouldn't trust the machine shop at this moment. Fitment of those seals is in most ( if not all?) workshop manuals.

[hotwheels]

Yea idk what they were doing. They mainly work on v8's and hot rod engines and what not. Being in america is something there not used to seeing. But regardless there nice guys and theres no other shop near me. Guess im stuck with these guys hahaha

[Spider]

 

I'm glad I read this, I'm just about to run a fresh engine build in. Can I ask how would you set up the engine so it's ready to go right away if the engine is modified? Sorry to hijack.

 

 

It's much easier with standard or known builds.

 

I set the static ignition timing while the engine is still in the engine stand if I'm not 100% sure, I'll set it on the retarded side a little (maybe 2 - 4 degrees at most).

 

In regards to the Mixture, fit the right needle or again, using charts or even Win SU and the Spring. Starting off with the Jet in the carb flush with the bridge, I wind the nut down 8 - 9 'flats' (around 1-1/2 turns). That usually gets one in the ball park near enough for that first run.

 

Upon starting it, I'm driving it right away, get it up to temp, then 3 or 4 wide open acceleration runs from 1500 to 3000 RPM. After that, return to the workshop, let it cool overnight, re-torque the head, set the tappets, check for leaks etc.

 

At this point, the engine can be run again, up to temp and fast idled (see below) for brief periods to check the timing, mixture etc, but try to keep them as brief as possible and I would suggest avoiding anything longer than about 2 minutes. If you need more time, take it out and bring it back, go again.

 

If the engine has a new or reground cam or just new or re-faced followers the idle speed should be set around 2000 RPM minimum for the first 20 minutes (or as recommended by the organ grinder). This is because fresh ground steels don't readily accept / absorb oil and so can dry run. The only lubrication the cam lobes and followers get is from what's thrown off from the Big Ends (even if the cam is 'cross drilled'). I also believe this is why cam life in the later cars, with the tall diffs, is poor, from continuous low RPMs.

[hotwheels]

Got it!! But is there a certain break in oil i should use?

[HUBBA.HUBBA]

Don't bother with the stem seals on the exhaust valves. I questioned it before and on race motor they are left off as the exhaust ones get too hot, getting brittle and break up. Also the oil going down lubes the stems. when its run in it'll be ok. Remember only the last minis had stem seals on the exhaust valves.
Minty lamb is a good source of needle profiles

Edited by HUBBA.HUBBA, 03 July 2016 - 08:53 PM.

[Spider]

On road engines I would always fit seals on the exhaust valves. Any oil getting on the exhaust valve seats will burn and make a real mess of them. Some cheaper oils can also burn on the lower stem, leaving a wonderful deposit of ash on them,,,,,

 

I use Penrite Running In Oil, but basically any non-friction modified Oil in a 15W40 is fine for running in.

 

 

but I wouldn't suggest leaving it for more than about 300 - 500 km (200 - 300 miles).

[skoughi]

I had to drain my rebuilt engines oil right after the initial run, as you described above moke, to fix leaking oil gallery plugs and was amazed at the state of the oil after this short period of running. It must've been down to the cam and bearing lube that I generously applied but it was horrible and very dark compared to what it was when it went in. I kept the revs below 3.5k ish for the next 500 odd miles giving her regular bursts of acceleration and have now started giving her a bit of beans. She needs more tweeking of the mixture but runs and accelerates lovely. We did a compression test the other evening and we got 190psi on all cylinders so I guess I can be happy with that. 

[hotwheels]

awesome, thanks for the replies guys, its mainly gonna be a road car, but theres always the possibility i might want to race it, see i messed up, i threw 20w-50 in it, I'm gonna drain it and put something thinner in, plus i went with just the cast iron guides instead of the brass/bronze ones

[Spider]

For a road car on unleaded fuels, stick with Cast Iron Guides. The Bronze ones, in their various guises are good, but 'fussy'. The Cast Iron ones are much less fussy and far more forgiving.

[govig]

Use a cheap 20/50 (like Wilko's) for running in and keep changing it. I change at 100, 500 + filter,1000 + filter miles then put some decent oil in like Valvolene, Morris or Millers with GL4 spec. I use Morris in various grades in everything but prefer the Millers for the Mini. 

[hotwheels]

Will do, but at the machine shop, they recommended a thinner oil to help seat the piston rings like a 10/30 but he didnt relize the oil shares the same oil as transmission.

[HUBBA.HUBBA]

On road engines I would always fit seals on the exhaust valves. Any oil getting on the exhaust valve seats will burn and make a real mess of them. Some cheaper oils can also burn on the lower stem, leaving a wonderful deposit of ash on them,,,,,
 
I use Penrite Running In Oil, but basically any non-friction modified Oil in a 15W40 is fine for running in.
 

 
but I wouldn't suggest leaving it for more than about 300 - 500 km (200 - 300 miles).

Are there any high quality stem seals that would be good for exhaust valves, I would prefer to have some on, to be honest.
Also anyone know of a way of fitting them with the head still on? I saw an episode of wheeler dealers that used compressed air to keep the valves in position, which I thought was quite good.

Edited by HUBBA.HUBBA, 10 July 2016 - 04:47 PM.

[carbon]

 

The machine shop are the ones who installed the main crank, conrods, and fitted the pistons to the block. So i figured they new what they were doing because thats all they specialize in. Compression ratio i believe is 10.1

Right now i dont know what castin it is but i would assume its the normal one.

What do you mean by chamber enlarging?

Thanks for the reply

The combustion chambers need significant enlarging to get you at a 10:1 ratio if you 'd use flat top pistons.
I wouldn't trust the machine shop at this moment. Fitment of those seals is in most ( if not all?) workshop manuals.

 

Flat top pistons in a 1330 with standard head chamber size will give CR of about 13.5:1.

 

To get this down to 10:1 you would need to either hog out the chambers by 10cc, or have the tops of the pistons about 100 thou below deck.

[mk1leg]

did you prime oil pump before first start up....(ie remove plugs and large banjo bolt top of block no4 piston) and pour oil down hole and spin engine over and repeat several times till you have a good oil pressure, replace banjo and spark plugs..

[Spider]

 

On road engines I would always fit seals on the exhaust valves. Any oil getting on the exhaust valve seats will burn and make a real mess of them. Some cheaper oils can also burn on the lower stem, leaving a wonderful deposit of ash on them,,,,,
 

Are there any high quality stem seals that would be good for exhaust valves, I would prefer to have some on, to be honest.
Also anyone know of a way of fitting them with the head still on? I saw an episode of wheeler dealers that used compressed air to keep the valves in position, which I thought was quite good.

 

 

I've found these quite good;-

 

http://minispares.co...|Back to search

 

but these aren't too bad either;-

 

http://minispares.co...|Back to search

 

There are a couple of ways it can be done without lifting the head, but you'll need to remove the rockers and then temporarily fit some spacers back in and tighten down the head (not necessary to torque it though) again before starting. You can get air line fittings, to hold the valves closed, but these are not fool proof. If the collets are stuck to the valve stem (as often the case), there's a very good possibility you'll lift the valve off it's seat trying to remove them and likewise when refitting the spring and top keeper, you need to be very careful you don't move the valve , which is easy to catch on the keeper. Also, be sure the piston in the cylinder you are working on is at BDC before connecting the air.

 

Another way, that I prefer, is to get some clean small rope and feed that in through the spark plug hole, about a metre will be well enough, keep the end tied off then put the car in to 4th gear and gently roll it until the rope is compressed against the head (and valves), handbrake on and go for it.