1098 Engine modifications

[bmcecosse]

Indeed - I think they were on the list earlier - although not on the latest list.

[John.n]

I have yet to sink the valve into the head. 320 thou?
ill have a look at the cam followers.
might just get away with lapping the faces a bit if there is very little wear.
Regards,
John

[bmcecosse]

NO!!!! Don't take chances with the followers. They have been run on a 3/8" lobe cam and now you are using a cam with 1/2" lobes. You NEED new followers with this MG cam.

[John.n]

my plan was to lap the surfaces of the followers to provide a fresh flat surface for the lobes of the cam. are they just surface hardened?
BMC guess you think this is a bad idea then...

Regards,
John

[brucek]

For what they cost new it's not worth the effort - always best to replace new with old - especially since you have invested in a better cam - why risk problems later when you can just fit new now whilst you have it stripped??

[bmcecosse]

It is a VERY bad idea......

[John.n]

new cam followers are about £20+ P&P

[brucek]

Is that too much???

[John.n]

I have been and had a look at the cam followers. they show hardly any wear at all. can just about tell where the cam has run against them visually. there is no dome worn into the followers or surface damage. I think I will re-use the followers.
Thank you for the warning though.

Regards,
John

[bmcecosse]

Not as much as that.... http://www.minispares.com/shop/classic/ ... spx?100103 But it's your engine....

[John.n]

I've fitted the cam and the timing gears today. went to fit the oil pump but found the original bolts are to long so I will have to cut them down a bit.
Is the scroll for the distributor drive the same on an MG metro cam as the original 1098 cam?
Regards,
John

[bmcecosse]

Yes! Be sure to prime the oil pump with 50/50 mix oil and vaseline.

[John.n]

I have cleaned and fitted the timing case this evening. I have been checking to see if the head will fit. dropped the head on without a gasket and have found the head rockes slightly on the block. I suspect that the gasket will take up this difference though.
trial fitted the water pump and fan as well and noticed that the fan is very close to the crankshaft damper.
Regards,
John

[les]

Be careful, if the head is not perfectly flat, don't expect the gasket to seal. Maybe the area around the studs is a bit proud or there is some raised areas where the waterways run.

[bmcecosse]

As above - you must slightly countersink the stud holes. If still not sitting happily - you need to find out why..... It wasn't sitting on the water pump - was it?? This needs to be filed down on the top surface. Just ease the fan away from the damper.

[John.n]

I didnt have the pump fitted with the head. I will investigate further. I will have a look at countersinking the holes to take any burrs off over the weekend. hopefully the head isnt warpped!
Regards,
John

[bmcecosse]

Ideally you need a surface table to check it - but try with a 12" steel rule.

[John.n]

tried the rule with a light behind. didnt show anything. I think there must be a raised thred in one of the holes like you have suggested. ill gauge how much of a difference there is.
any thoughts on engine test stands as the car is not ready for the engine!
Regards,
John

[bmcecosse]

Test stand ? What for ? Running the engine without load will prove nothing... But you can lash it to a bench and give it a whirl - but I can't see the point.

[John.n]

just to make sure pistons and valves dont meet and oil dosent leak anywhere. then I will paint the engine. not using for a performance test.
Regards,
John