Punto (Mk2/2b) advice and guidance motor overhaul

[nigenius]

Hi everyone

Great forum been a member for a while but first time posting.

I have a Punto Mk2b/3(not sure) 188A5. It seems i have a valve issue as oil is making it past a valve on cylinder 4 (visible oil flow with plug removed). I am preparing to strip down motor and replace head gasket and valve seals etc. Are there any pointers/sugestions which anyone can offer while motor is apart. Also are the expansion bolts reusable?

Thanks

 

[Brendan W]

Before opening the motor I would do a wet and dry compression test as a general health check and to rule out broken rings as the source of the oil. Are there any signs of headgasket failure like oil in the coolant or coolant in the oil. I would try to be sure the cause of fluid was in fact valve seals and not the headgasket.
Presume you have a 16V motor. Best practice is to replace headbolts. They're not expensive in the context of rebuilding a head. I hve reused them on 8V motors. But you are taking a risk that you will have to do the job all over again.
When the head is off have it checked for flatness and skim if in doubt.

 

[nigenius]

Hi Brendon W

Thanks for the reply. Could you pls explain Wet / Dry test? Yes it is a 16V 1.2. there is no coolant leak either way. I am replacing head gasket because I have to remove head so as to replace valve seals.

 

[Brendan W]

You do a compression test with the motor and then do a second one with a small quantity of oil added to each cylinder. If there is an improvement in the pressure you could say that the rings are worn.
Is the plug on the leaky cylinder wet with oil? What are the other plugs like?

 

[nigenius]

Hi Brendan

thanks again when piston 4 at top and plug removed you can watch the cavity fill slowly with oil using a torch. at present i am using 5 litres of oil every 2 weeks. but i have another problem no-one has stock on cylinder head bolts and i am not sure if the current ones ones were already reused by previous owner.

 

[varesecrazy]

Hi,
TBH - IF the rings are damaged / worn badly;

you'll be removing the sump , and undoing the bearing journal / BIG end,
and sliding the piston UP + out of the bore,
then honing the bore,
replacing = rings, bearing journal + (Sump pan ?- our's rot through @ 8 years old - climate), then the HG , bolts, (waterpump + thermostat ??)

with a shopping list like that you MAY be better-off sourcing from overseas and shipping,

Charlie

 

[Brendan W]

Hi Brendan

thanks again when piston 4 at top and plug removed you can watch the cavity fill slowly with oil using a torch. at present i am using 5 litres of oil every 2 weeks. but i have another problem no-one has stock on cylinder head bolts and i am not sure if the current ones ones were already reused by previous owner.

Sounds like the oil is coming from above which could mean headgasket, valve seals or a warped or cracked head. On way or another the head will have to come off.
There are UK based suppliers who ship worldwide.

 

[Ziggy122]

Id say doing a sump off and cylinder hole is possibly best way
Ensure new compression+oil rings fir that cylinder if the wet compression test is higher vs dry

Ziggy