Aurora 4.0l / Izuzu 5 speed swap into 88 coupe (Page 51/102)
cptsnoopy DEC 04, 03:09 PM
I dropped off the parts car panels to see if the media blaster guy can remove the old paint without tearing into the plastic/fiberglass. I looked at some work that he has done and it looks promising.

On a sad note, the front bank of the Aurora just developed a smoking issue. In my limited knowledge of the subject, I suspect it to either be oil getting pulled through the intake valve seals or water is somehow getting into one of the front cylinders. More likely oil though since I have been idling the engine at high vacuum pressure for a long time. No smoke at all for at least an hour of on and off engine run time since I first started it and then suddenly quite a lot of smoke. Hmmm, what to do?...
cptsnoopy DEC 15, 01:15 AM
I ran the engine again today for about 30 minutes. It does not smoke at all until it is warmed up and I "blip" the throttle. After looking at the front bank intake valves, I noticed that the suspect #8 cylinder seemed to have a little moisture (possibly oil) on the intake valve. It would make since that this is why this engine was pulled for warranty and eventually I ended up with it.

Can the valve seals be changed without removing the heads? If so can anyone in the know explain the process? I may wait until the car is driving before tearing into it just to make sure the rest of the drive train is working and there are no clearance issues.

charlie
Will DEC 15, 07:18 AM
You can. I've done it. You need to pull the cams, though.
cptsnoopy DEC 15, 01:32 PM

quote
Originally posted by Will:

You can. I've done it. You need to pull the cams, though.



Thanks for the info Will. I will be pulling the engine out after a quick road test to see if there are any other issues. Then I can repeat what I had to do to spike the valves...

charlie
Russ544 DEC 15, 03:43 PM
Will,
I was just looking at a bare N* head I have here at the shop. it looks like vlv seals could be swapped out with the head on the block alright, but it would require that you buy or build some pretty tricky tools to do it with. what did you use to compress the valve spring and remove/reinstall the keepers? and how about the stem seal and spring seat/cap? looks like a small slide hammer with a hook on the end could be used to snag the hole in the side of the seat/seal cap to remove them off the vlv guide?

Russ
cptsnoopy DEC 15, 07:56 PM
I talked to Alan for about 15 minutes concerning the possibilities. He felt pretty sure that I will need to pull the head to have a valve guide repaired/replaced. That may end up being easier than trying to figure out a system to replace a valve seal with the head still on. I am hoping that since the engine has so few miles on it the head bolt threads may survive. The only other "trick" will be to find a N* mechanic that can look at the head and determine what the problem really is and fix it correctly.
Will DEC 16, 11:31 AM
Do you mean seals or guides?

The seals can be replaced with the heads on the engine... remove cams and lifters, pressurize each cylinder, then R&R the seals. I used a cotter pin puller and "custom" thick wire hooks, as I recall. I had a thin wall polyethylene tube whipped up to protect the lifter bores and milled a slot in the side of a piece of 3/4" pipe to use to remove the retainers & valvesprings.

Allen Cline has some advice on how to add some RTV to eliminate a potential leak path... I'll try to pull that later.

The seals themselves are unlikely to fail as they are top-of-the-line models with spring retention.
Russ544 DEC 16, 12:29 PM

quote
Originally posted by Will:

The seals themselves are unlikely to fail as they are top-of-the-line models with spring retention.



That's true of course, but this was a warranty motor so it may have had a seal damaged when the factory installed it.

Russ
cptsnoopy DEC 16, 01:50 PM
Hi Will,

Alan thought it most likely to be a problem with a valve guide. But as Russ mentioned, he allowed for the possibility of a damaged seal during assembly. It would be nice if I could remove the seals before pulling the head bolts and examine them. Alan also mentioned that he had one head with similar problems that had a casting imperfection. It was a small hole in the head near the seal that would only pass oil when the engine was up to running temp. I hope that is not the case here.

Thank you guys for the help and support.

charlie



On a side note, do either of you know the difference between the factory L47 and the "massaged" version made specifically for the Shelby Series 1? The Shelby engine can be purchased new for about $3K. I have heard it has different cams and can rev higher. But, I have also heard it was used with a supercharger so they may have lowered the compression ratio a tad. I have no idea if it would be plug and play in my car.
Russ544 DEC 16, 02:39 PM

quote
Originally posted by cptsnoopy:

Hi Will,

Alan thought it most likely to be a problem with a valve guide. But as Russ mentioned, he allowed for the possibility of a damaged seal during assembly. It would be nice if I could remove the seals before pulling the head bolts and examine them. Alan also mentioned that he had one head with similar problems that had a casting imperfection. It was a small hole in the head near the seal that would only pass oil when the engine was up to running temp. I hope that is not the case here.




it's not a problem to remove the springs with the head on. just remove the intake cam and offending lifter, set a deep 5/8 or 3/4" socket on the spring retainer and give the socket a modest smack with a hammer. this compresses the spring long enough that the retainers just fall out. I always remove the retainers this way. _replacing_ the retainers will be the harder part however .
you alread know which cylinder is the problem, so just pop those springs off and you'll be able to check the seals as well as checking for excess clearance in the valve guide. I can make you a tool to replace the springs and keepers without too much trouble if you like.

Russ

[This message has been edited by Russ544 (edited 12-16-2008).]