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Re: Engine in bits for a rebore-anything else worth doing?

Posted: Sat Aug 17, 2019 12:41 pm
by philthehill
The Gates V6271 fan belt is the correct fan/drive belt for the Marina/Ital.

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Sat Aug 17, 2019 3:09 pm
by ndevans
A couple of hours on charge this morning whilst at parkrun seems to have sorted it, so thanks for that suggestion. There's no hint of a shriek as the revs rise now.
I've had a run in it and got it nice and hot, then re-torqued the head. However, there's still a small weep of oil down the side of the block, at the same place. I think that it may not be the head though. The top bolt on the timing cover appears to be touching the block, and I thought that may cause oil to propagate out and onto the block. I've had the bolt out, and the washer was missing, so I've replaced it with two. It now goes in nice and tight, and the end of the thread is clear of the block. After a short run, there does not seem to be any oil leaking. Early days yet though, I will keep a close eye on it. I think there definitely was a leak from the head, before I took the head off, as I could see a bead of oil forming between the head and block.
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Cheers N

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Sat Aug 17, 2019 4:24 pm
by paul 300358
It was worth doing whatever the oil leak as you have sorted out the rockers. Well done.

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Sat Aug 17, 2019 4:46 pm
by ndevans
Well I certainly have spotted and sorted a potential issue there, so there's a silver lining l suppose. Whether the oil weep is sorted or not I don't know, time will tell. If it is the timing cover/front plate, and it's still happening, I might just live with it until it's run in.

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Sun Aug 18, 2019 10:55 pm
by ndevans
So after a bit of mileage this weekend, it appears that the oil leak from the head is not cured. There is a definite weep from the same area of the head, just under the forward most port of the exhaust manifold.
It's not exactly gushing out, it's a drop or two forming after about 20 miles of running. So do I live with it for a couple of weeks, while I get the engine run in over say 500 miles, then get the head off and have it squared up, or should I just get the head off and get it sorted?

Cheers N

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Mon Aug 19, 2019 12:18 am
by amgrave
Check to see if the head is not sitting on the top edge of the water pump and stopping it seating fully on the block top face, it does happen with some water pumps apparently.

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Mon Aug 19, 2019 7:06 am
by ndevans
I will check that, but it's the same block/water pump/head combination that I've been using for 3 yrs without issue, so I'll be surprised if that's the cause. But thanks for the suggestion, I hadn't thought of that!

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Mon Aug 19, 2019 8:17 am
by philthehill
I would be in no rush to strip the head off again.

After 500 miles I would retorque the head nuts when cold.

I have known heads to pull down even after many miles of running when a torque wrench is applied to the head nuts.

It is not only on Minors does it happens - my Rover 220 GSi had the same problem and I ran it with a slight weep for several thousand miles with no detriment to the engine.

I would just monitor the weep and enjoy the ride.

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Mon Aug 19, 2019 5:57 pm
by ndevans
Ok, thanks Phil.

What I'll do is I'll run it in over 500 miles or so, then re-torque again, and see if it improves.

When you re-torque, how do you do it? Just take each nut up to 40lb-ft, or just past?

Cheers N

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Mon Aug 19, 2019 7:13 pm
by philthehill
If I remember correctly you have the early non marked cylinder head studs and non flanged nuts.

I would firstly tighten the head nuts to 45lbf ft in the order laid out in the wksp man.

The reason I give the above figure is that:-

The cylinder head studs for the 10V and 12V engines (pre 'A' Plus) are the same and have the same part numbers - .stud short either part number 51K280 (NLA) or CAM151 and stud long 51k279.

The Marina factory manual Pt No: AKD7555 states that the 1275cc 12V engine head stud/bolt torque should be torqued to 50lbf ft (the 10V torqued to 40lbf ft).

The later cylinder head studs are made from better quality materials and are marked on the top with a letter or have a pointed top. They are used with the flanged nuts.

The torque setting for the later better quality studs & flanged nuts is still 50lbf ft.

Therefore you can set the cylinder head studs to 50lbf ft, but I would recommend that you retorque in two stages 45lbf ft first and then 50lbf ft.

Phil

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Mon Aug 19, 2019 7:18 pm
by ndevans
Yes, correct, they are the plain, non-flanged nuts. Ok thanks, that's what I'll do. If that doesn't cure the oil weep, is it head off and skim time?

Cheers N

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Mon Aug 19, 2019 10:22 pm
by Myrtles Man
Am I right in thinking that when you re-torque after the bedding-in period it's good practice to unscrew a quarter turn before torquing up to the specified figure?

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Mon Aug 19, 2019 10:32 pm
by oliver90owner
Myrtles Man wrote:
Mon Aug 19, 2019 10:22 pm
Am I right in thinking that when you re-torque after the bedding-in period it's good practice to unscrew a quarter turn before torquing up to the specified figure?
Correct. That is standard engineering practice.

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Tue Aug 20, 2019 10:19 pm
by ndevans
Current state of play. It's a small dribble. I'll live with it until the engine is run in, then re-torque. If the problem doesn't go away, I'll consider getting the head machined.
Cheers N
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Re: Engine in bits for a rebore-anything else worth doing?

Posted: Wed Aug 21, 2019 10:13 am
by paul 300358
Why not fit a decent modern composite head gasket? I got mine from my local Mini dealer Minimine.

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Wed Aug 21, 2019 10:33 am
by ndevans
I had a composite head gasket originally, that's what failed and caused me to have the head off in the first place. I then discovered scores in the bores, so had the block re-bored.
I thought that copper gaskets were supposed to be better than composite anyway?

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Wed Aug 21, 2019 1:26 pm
by philthehill
The Mini Spares copper head gaskets gives the best value for money and is fitted to my Minor.

The head gasket originally fitted was one of the very expensive head gaskets

http://www.minispares.com/product/Class ... HT189.aspx? 100401&ReturnUrl=/search/classic/head%20gasket.aspx|Back%20to%20search

At the last rebuild I used the Mini Spare/Payen head gasket and I have never had any problems and that is used with a very high compression ratio and good oil pressure.

Having the block and head and block skimmed does help.

As regards any other make of gasket I cannot give an opinion as I only use what I know works.

Phil

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Wed Aug 21, 2019 2:24 pm
by PoolGuy
philthehill wrote:
Wed Aug 21, 2019 1:26 pm
At the last rebuild I used the Mini Spare/Payen head gasket and I have never had any problems and that is used with a very high compression ratio and good oil pressure.

Phil
My engine builder recommends the same gasket, it’s currently out of stock but they have a stock alert system https://minispares.com/product/classic/GUG702506HG.aspx

It appears to be the same gasket that Roversport supplied back in the day.

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Wed Aug 21, 2019 3:31 pm
by philthehill
The Payne AFG460/Mini Spares GEG300 (copper) is currently available and in stock according to the Mini Spares parts web site.

https://minispares.com/product/Classic/ ... o%20search

Poolguy

The head gasket in your link above is only suitable for small bore engines and not 1275cc engines as per this thread.

Phil

Re: Engine in bits for a rebore-anything else worth doing?

Posted: Wed Aug 21, 2019 3:38 pm
by PoolGuy
Sorry, this has dragged on so long that I’d forgotten that it was a 1300 build.