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Valve stem seals. Engine out?

2374 Views 10 Replies 3 Participants Last post by  Alfisto Steve
I lent my 164 to someone today, and as they drove off I noticed puffs of blue smoke on the up-changes.

My 164 did this the day I bought it, and in the months since, I've had a couple of bottles of oil-seal-rejuvenator in the system. So, obviously that hasn't worked :(

I would like to fix this (puffs of smoke = embarrassing), but it's a matter of deciding how much else to fix at the same time. Here is a shortlist of jobs to do:

- Valve stem seals, heads removal required due to valves being deep in pockets and therefore not compressible with heads in place?

- Seals behind cam pulleys, cambelt and tensioner

- Possibly sump, rear main, or other oil leak onto exhaust pipe under engine

- Air conditioning compressor replacement

- Clutch very heavy, not nice around town. Ruled out the hydraulics already. No record of clutch ever being changed by previous two owners who were both good drivers, so probably near the end of its life now (I knew a Croma that did over 400,000km on its original clutch). Might even change the gearbox as well, since the gearchange has a strange metal-on-metal feel despite oil changes, I think the sliding hubs are simply worn-out. It doesn't crunch or whine, but the change quality is very notchy and seems to allow a 1-in-4-times selection of reverse, frustrating for three-point turns in the middle of the road!

It's getting to the point where I'm thinking it may be practical to remove complete engine/transmission/subframe from the car, particularly as I want to change the clutch and would like to clean up the engine bay properly as well, replace fuel pipes, air conditioning hoses etc. I suspect that with suspension disconnected (oh, that needs new bushes too), the whole subframe will unbolt and be left behind as I raise the bodyshell. I have a garage that I can dedicate to the rebuilding process, so it can be done over several months if necessary.

Drastic, but what do you think... Easier to get the heads off that way? Even the cam seals (a simple job) looked unduly fiddly with the engine in place and it just seems that with it out, those jobs will take half the time.

Should I take the engine completely to bits or leave pistons/liners in place? Engine has quite high mileage (235,000km) but seems to run great with no smoke on acceleration.

What parts do I need - and how much is a head gasket set worth? I've never tackled a V6 before. I imagine the head set(s) will be about all I need, plus maybe another seal or two. Or should I attempt to hone the bores/replace liner seals?

Alternatively would I be better off to remove heads with engine left in the car?

Sorry for the big questions but obviously, this is a project I would like to plan before I start. I've had so much fun driving the car in the few months since purchase that I haven't wanted to take it off the road for the clutch replacement etc. I spent very little when I bought the car, so I'm happy to spend on parts.

Thanks,
-Alex
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I pulled my son's heavy-clutch engine out with the 5-speed attached. We redid many things with the engine out, including replacing the fuel line splices on the firewall. It was a breeze because we had an engine hoist. A bit fiddly to do the trans. input shaft bearing (you should think about that, too), but that was the actual "proximate cause" of doing any of the work. We found lots of stuff to do, and discovered that the P.O. had left off the flywheel cover and as a result enough dirt/oil paste had accumulated on the clutch friction disc that one side (only) had been worn down through the wear indicating grooves in the friction material. All in all, it was a rewarding experience and a good time was had by all.

Alfisto Steve's pointer on lowering the tranny mount to gain access at the cam gear area for seal replacement is a great one for in-place work. The "rope trick" applied to in situ valve seal replacement might be worth considering unless it is exhaust valves which are the problem area and they were done with seal-less exhaust valve guides. (Stuff soft rope into the cylinder and then manually press it against the cylinder head to keep the valve from dropping when the spring and keepers are removed for seal access) But you might find some usable heads to have the seals re-done and maybe touch up the valve surfaces, and then simply swap out the heads. I might argue that you should have the starter rebuilt at the same time, pulling the engine for ease of access to everything.

Complete engine gasket sets are available in the US for prices across the range (from under) US$150 (Spanish ADJUSA -- may be Milano 3.0 version) to ~US$600 for OE Alfa.

Michael
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Pull or drop full engine/tranny set up

I would either drop whole sub frame and engine/tranny set up and do the full Monty year 17 maintenance package of whole drive train/suspension and engine bay or just pull engine and tranny assembly out the top and do a modified mini maintenance package.

Along with clutch replacement you will need to verify tranny condition even if quiet now and be sure it has overload version input shaft roller bearing.

If lower end is strong probably just freshen heads with valve job, seals and guides if needed.

Plan on water pump change, injector cleaning, reface flywheel, replace rear main and front crank seal if it shows any leakage.

Also look at changing a/c heater blower motor and a/c compressor clutch pulley bearing. Freshen up starter and replace regulator/brush set in alternator.
Time to revive this thread. Not a lot has changed in the intervening two years - except I now have another 164 to think about. For the first 164, I obtained a replacement engine that has already had the necessary work carried out. Haven't had time to change the engine yet, but have bought an engine crane just to get the replacement engine home on a trailer - a mission that worked out perfectly.

The second 164 has the usual problem of needing the valve seals replaced. I'm a little reluctant to remove the heads for the full service. Though, since I now have an engine crane, maybe it's easier to take the whole engine out.

My question is - referring to Michael's post above regarding the 'rope trick' - is there a suitable tool to compress the valve springs? Is it safe to 'shock' the valve cap (to release the split cotters) when the valve is held up by rope fed into the combustion chamber and compressed by the piston?

Reading this thread http://www.alfabb.com/bb/forums/164-168-1991-1995/2274-valve-seal-replacement.html I see that a better option might be to pressurise cylinder (with screwed-in fitting from compression gauge) using my big new air compressor. I imagine that if I make up some kind of forked, cup-shape tool, I should be able to lever spring cap downwards against pressure of, say, 150psi in cylinder. And if that levering doesn't work, a few sharp shocks would be less dangerous against the air pressure than against the rope.

Has anyone achieved valve stem seal replacement without removing cylinder heads?

Amazing how time flies - two years and 10,000km, and no progress apart from more money, more tools, and more cars to work on...!

Thanks,
-Alex
Alex, I haven't done it myself, but I did acquire a valve tool from the P.O. of my last pair of 164s. Apart from the necessary timing belt work and purchase of head gaskets, I didn't find it too gruesome to R&R the heads on our car with a head gasket failure last year. Of course, -that- may have been two years ago, too. Time does fly.

Michael
Michael, thanks. Sorry for the stupid question but what does the valve tool look like? Is it a claw-shaped compressor to fit around valve spring or is it a conventional compressor (giant G-clamp shape which requires head removal)?

'valve tool' in the context of other engines I've worked on was a hook-shaped tool to hold tappet buckets depressed so that shims could be changed, but this doesn't apply to the V6 as far as I know, because the shims are under the tappet buckets for the intake valves.

-Alex
I think the one I got from him is the International Auto Parts item #35755
Check out this link:

Valve Spring Compressor Adapter for Alfa

I have never used it, and don't know exactly what else might be needed. But I'm pretty certain you'll get more useful info from others soon. I think you use a tool which screws into either the plug well or some other spot on the head, and then pull up on the lever to compress the valve spring. But I don't know.

Michael
Valve tools

I think the one I got from him is the International Auto Parts item #35755
Check out this link:

Valve Spring Compressor Adapter for Alfa

I have never used it, and don't know exactly what else might be needed. But I'm pretty certain you'll get more useful info from others soon. I think you use a tool which screws into either the plug well or some other spot on the head, and then pull up on the lever to compress the valve spring. But I don't know.

Michael
That Nylon adapter is used with universal valve spring compressor to prevent marring tappet bores on V6 12v intake valves and int/ex bores on 4 cylinder engines. The trick of course is to hold valves closed whether by rope. air pressure, piston at top and then have a way to attach a lever to head to push down on nylon adapter or factory adapter with heads on engine.

Factory tools for removing valves are shown in 8th picture from top in Jason's post http://www.alfabb.com/bb/forums/164-168-1991-1995/31993-special-tools.html Picture 13 is factory tool 1821122000 Tool Removing/refitting cotters is similiar to IAP nylon adapter but it attaches to lever and again goes down inside tappet bores to prevent damaging bore.

Factory tool requires valves to be held closed by inserting block under heads of valves and then screwing on retainer with eye hook down through spark plug hole. Pretty hard to use factory tool with heads on V6 engine. On 4 cylinder models there is an adapter that attaxhes to cam bearing cap which maybe adaptable to V6.
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Thanks for the advice on tools Michael and Alfisto Steve.

Something tells me I'll be using my shiny new engine crane to lift engine out the top (the way I've always said it shouldn't be done!) and then removing heads to do a proper job in probably less time than the fiddly-sounding valve spring removal in-situ. Basically, everything I planned to do to my first 164, but never got around to doing. I'll report back on this thread when I actually make some progress.

-Alex
Alex, The head gasket replacement I mentioned doing above was accomplished with the engine in the car. I pulled the false firewall, undid the motor mounts, and rotated the engine forward per discussions on the board. I don't recall whether I let the transmission mount down, but I don't think so because it was an A/T car and not a 5-speed. I think I just rocked the block/transmission toward the front bumper by jacking it up from the rear. DO NOT DO THIS CARELESSLY or you -will- destroy your expen$ive right front motor mount. No. I'd -never- have done that. At least not that I'd admit without severe sympathy and some helpful beer.

Michael
Ah having spare parts sure does help the process. I try to keep a spare set of heads reworked and ready to go but I am down to one reworked front head now that I have built two engines up recently of which one was short a rear head I had given/traded to a friend in exchange for a new SD-709 compressor some years ago. His old head was rebuilt and used on another friend's engine. Finally was able to install somebody's rebuilt head back on the engine. My spare front head (not the really the one I now have in my stash) I got in a 164S parts buy some years ago but I never ended up with a spare rear head.

Musical parts are handy.

I do have a spare as is condition Pick-N-Pull engine with both heads on it but haven't removed/rebuilt heads yet but probably ought to do rear one before I need to repalce another set on a rescue project.
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