correct honing?

[Dave_EH]

I'm getting close to installing a reconditioned 179 engine - it has yet to be started.  Removal of the head reveals that there is a lip at the top of the cylinder bore in a couple of the cylinders... it looks like when it was honed the top 4 or 5 mm missed out.

Its very minor but can be felt with the finger tip.

My questions are:

has anyone heard of this before?
can this lip be honed out while the engine is assembled?
so close to the top of the bore - will it even make a difference?

The block has been acid dipped, honed and painted, but instead of running the risk of installing a "dud" motor should i get the hot parts (brand new cam, straight cut timing gears, new lifters, twin point dizzy, yella terra head) changed over to my existing stock motor?

I have a photo of the lip but don't have a means of posting it right at the moment.

Hope someone can make some sense of my rambling description

Dave

[ACE]

Hi Dave_EH,
Was the motor reconditioned by a professional?
If so take it back and show him!
The lip at the top of the bore should have been removed with a ridge remover before honing.
In some cases if it is not removed it may cause the top piston ring to break.
Regards ACE  
O yeh why did you remove the cylinder head if the motor is reconditioned?

[Dave_EH]

There is a little more to the story...

I got the motor from the trading post.  The bloke had the block work done professionally, but dialled in the cam and did the new rings and bearings etc himself.

From what i can work out he needed some cash in a hurry...and needed to sell the engine.

The head wasnt on it when i bought - I've since had a full reco on it, and the bloke showed me how the ridge was there - he wasn't too happy either.

I picked up the engine with new lifters, 30/70 power boss cam, new bearings, new rings, the straight cuts, dizzy, new fuel and water pump and YT head etc for $400, which i thought was a steal for the internals at lest.

Being a little green to this sort of stuff, the engine probably isnt all that drivable anyway - but being young I guess i was thinking bigger is better.

i picked up a set up triple SUs for a steal at the same time so i thought it would be a killer combination - esp with the steel crank of the 179.

Any thoughts...what would you do?  The existing motor was recoed by repco with low milage.

regards
Dave

[ACE]

O.K the ridge is there because the "reconditioned motor "has done some mileage.
It should be alright to use as is. and there is nothing special about a 179 crank.
Regards ACE  

[Dave_EH]

No worries Ace.  The reason for the overhaul was apparently due to a cracked ring - and taking into account what you have just said - seems likely...and maybe (unfortunately for me) likley to happen again

I may have been a little vague with my description of "lip" as well - its more of an indent.  If you were to put a straight edge against the bore there would be a small semi-sphere behind it.

appreciate the advice
Dave

[Martin]

Dave,

I've only just seen this post.  

The cause of the lip will give you some idea of the problem you have:

In a worn engine, both the bores and the rings are worn by contact with each other.  Because the rings do not go right to the top of the cylinder, a lip is left at the top.  You'll find the lip is about as deep as the distance from the top of the piston to the first ring.

So it seems to me the engine may not have been bored out in the reconditioning process.  Maybe new rings and bearings were fitted, and your Trading Post seller described this as "recondtioned", but I would bet the block has not been rebored.  Probably the same pistons, gudgeon pins and little end bearings went back into the motor.  

The lips can be honed out without dismantling the engine further - there is a manual honing tool designed to do this job.

As Ace says, if it's not done there is a risk that the new rings might foul the lip and break.

You might want to have a bit of a closer look at your recon motor or you might be disappointed when you fire it up and it burns a bit of oil.

Martin

[Martin]

Dave,

I've just read your reply to Ace properly.  

If the lip is indented, rather than "proud", then I'd say the honing of the original lip was done - but over-done - honed too much.  In anybody's language, that would be pretty careless workmanship.  And it still suggests to me the block was not rebored, so the bores may still be a little oversize due to wear and it will burn oil prematurely.

Martin

[Dave_EH]

Thanks Martin,

 I guess i may have to learn this lesson the hard way.  I will try and get a photo up some time - I just don't have photo bucket or anything set up yet.

The exististing stock engine seems quite strong - it was built about 9 or 10 years ago by repco and has been bored out - to 192 i think.  Its only done about 15 000 miles though - and has sat idle except for the odd fire up for the last 5 years.  Still not registered yet so time will tell whether it burns oil on a trip or not.

Still at uni and not much cash to spend - so I thought i might swap the motors as a cheap way of a bit of fun.

However, I may be better off having both engines disassmebled with the goodies put in the better block - big dollars in my world though...and a little scary!

Anyhow something to chew over... maybe the YT head with twin strommies might be all I really need?

Appreciate your help - it all helps me learn a little more!

Regards
Dave

p.s how'd you go with the gearbox

[Martin]

Dave,

I've got a recon box on the way from Vic at the moment.  Won't know whether I've got a gem or a lemon for a couple of months, tho, until after it goes into the car (planning ahead   )  Thanks for asking.

Cheers