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Discussion Starter · #1 ·
Hi guys
I did a top overhaul with the engine in situ of course , removed a ton of stuff, a lot of cleaning work and carbon removal then found out then the cylinder liners can move when I turn the pistons to decoke them ..is this normal to be so loose and can I just fit the cylinder head and pray it doesn't leak ..as I'm doing it at home a complete overhaul with the engine out might be bit tough . Just some pictures for your info what's involved doing it in a car porch .
 

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Discussion Starter · #4 ·
Haven't yet taken a picture of the liners coming out but I'm wondering whether the seals will still be ok ..they were ok before I took out the cylinder head
 

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Don't even try it, they will leak. If you want to gamble pull the liners and have them honed and tapered at the bottom. Replace the rings and do your best to clean the block where the liners seal. You can slip the tapered liner with new seal over the new rings, with some sealant.
I am interested to see what other people would do.
 

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Discussion Starter · #6 ·
Thanks for your reply alfettaparts 2.More pictures ..the liners can't come out and they stop at the same point ...can someone tell me how many seals are there ..based on the parts diagram there should only be one sitting on the middle support of the liners which I could not see but think it's stuck to the ridge if the liners ..I can feel something..
any chance if I blow with an airgun and clean as thoroughly as possible ,apply some some sealant and pray that it will not leak ...as I mentioned it difficult for me at home to remove the engine and I'm sure the sump could not be taken out without shifting the engine or taking it out ..the sump is in
 

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Discussion Starter · #7 ·
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Actually it seems all the liners could move which testify the minimal rust in that area
 

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It's a wet liner design. You have disturbed the sealing, so bummer ... pistons out time (I wonder if you removed the liners with the pistons still in them if you could just clean and install new liner o rings?)

Pete
 

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Its possible the liner is catching on the rings where the piston stroke ends?
Try a couple of levers each side of the liner, there is no reason they shouldn't come out.
Failing that its sump off and pistons out. The sump will come off with a bit of swearing and holding your tongue in the right place.
There is just one very thin O'ring that seals the liner, I would advise against trying to seal it. Even at a 50/50 chance it would be really crappy to put everything back together and have a leak. I hate doing things twice.
Look at it as an opportunity to fit new rings.

If you have a machine shop hone and taper the bottom of the liner you can slip them back over the pistons.
 

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Discussion Starter · #10 ·
Yup I was hoping not to remove the engine from the engine bay ..I was wondering any possibility of pulling out the liners and after checking refitting the pistons and rings from below if I can get help holding the liners .....if not then engine or sump out , piston out almost a complete overhaul ... ..which is a good thing too .

Can I ask what's that black thing I see holding the liners . .since the liner has only one o ring seal which is still attached to the ridge of the liner I believe what is this I see inside
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If you want to reuse rings, pull liners out after undoing connecting rod caps from below, so pistons stay in liners and come out too.

If you have good rings, disturbing them will potentially be a backward step.

Pete
 

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Discussion Starter · #12 ·
Yes Pete .
.looks like I have to head that direction . I just hope the sump can come out without shifting the engine too much ..as alfetta2 said it can come out with a bit of swearing ..hahaha ...will be my biggest job to date at home on a fairly big engine ..I've done motorcycle engines at home which are small even a 1200 guzzi twin..(1 am not an auto mechanic by trade /just a hobby))the gtv6 big ends are definitely ok as car was running well until one plug developed a coolant leak .
 

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Discussion Starter · #13 ·
Ok here is the latest just for those who might do this job later. I've managed to pull out the piston half way where I can clean the ridge area where the o ring sits and also the taper area on the block where the o ring rest on the block side ..this seems more acceptable and should work without taking out the engine or removing the conrods from below.the new o rings can be installed from the liner top rolling it down
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Well, without sounding like a broken record I would remove the liners, have them honed and tapered at the bottom. New rings and slide them back over the pistons. I have done this before on multiple occasions with no problem so if I was in your position I know that fix works.
The only thing I can see wrong with your fix, is the o'ring being deformed when stretching it over the liner but only you can judge that. Use a sealant and prey to the god of you choice :giggle:
 

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Discussion Starter · #15 ·
Hahahahaha I like you Alfettaparts2 ..Yes I did think that will happen and it seemed it did ..however upon further inspection it did sit on the tapered area and I can confirmed once you stretch the o ring it seemed to be not as tight as the old o ring ....it doesn't sit so tightly on the ridge but once i push the liner down I can see it sitting on the tapered area if the block ..normally o ring should be very pliable and return to it's firm but this particular ring is so thin and I don't know whether it's some special characteristic material I ring . .maybe I should just do what say and take the bloody engine out ..which means mobilizing eqpt i don't have.
 

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Discussion Starter · #16 ·
What kind of o ring are this? Any material specialist knows whether they will fit better exposed to hot water/coolant
 

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Discussion Starter · #17 ·
A question alfetta2 .? If I take out the liners and do the honing and tapered at the bottom it will help in inserting the pistons ..do you still remove the Conrod from below to take out or just take out from the top ..how do you compress the piston rings later to insert from below the liner ...am I correct that's what your suggesting or I misunderstood you..is there enough space around the block to fit the piston ring compressor , or the machined taper will make the fitting of the pistons much easier ....just wanted to be sure to do the right thing based on your experience.
 

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If you taper the bottom of the liner you can slip it over the rings with some careful finger work, gently working the rings into the taper/liner. Patience is key. No tools required.
In your situation its my opinion that its really a 50/50 call between doing it this way or removing the sump and conrods.
I stress this is only my opinion. Read:not my fault when you mes it up LOL
I am glad you appreciate my sense of humor, I think its often lost online.

If I may indulge. I'm on my last 24 hours of hotel quarantine after 14 days living in a box. I think tomorrow night at midnight I can walk down to Mc****burburger, scarf down half a dozen burgers.
I have done what I suggested a few times at work (don't work there anymore), for cars with a split liner, and I think one with broken rings.
One time we were at Sandown raceway for the weekend. Our car had been dyno tuned the prior week but the mixtures and timing had been cut down to much causing a liner to split in Friday practice. Friday evening we set about removing the head while the engine builder set about readying a new liner for the morning. I think the gate opened at 7 am Saturday and we made qualifying before lunch going on to finish second for the rest of the weekend behind a Lotus 7 that was impossible to match.

Never glue a race engine together.
Enjoy the times when they are hard.
Tell the people in your life what they mean to you.
 

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Discussion Starter · #19 ·
Yup I know it's just your advice ..no issues ..I will do the practical side if it and determine which way is safer without going the while route if possible ...may I ask what kind of box. Are you referring to where you lived for 14 days ?
 

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Heck, just rip the sump off and remove the piston and liners as an assembly.

There are no short cuts when working on Alfa Romeos, and you have already said you don't want to go to the expense of new rings and honing the liners ... the obvious answer is to undo the connecting rod bolts so the liner with the piston still inside can be removed. New O-ring slapped on and liner and piston re-installed, con rod bolts torqued and on to the next cylinder
Pete
 
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