1995 Q45 HLA related question

[mpaton2]

I'm preparing myself to change or clean out some HLAs on my 1995 Q45. The ticking of 4 or 5 of them is testing my mechanical sympathy to the limit. I've seen articles on cleaning them, but my question is really about removing them.

Is it possible to position the crank to a point where the piston is down the bore and the cam for that lifter is not pressing on the follower, and then use a suitable tool to push the valve far enough through the guide so that the follower can be lifted off the HLA, and then the follower and HLA can be removed?

I understand that "a suitable tool" probably won't be some pry bar lying around.

Or must the cams be removed?

In either case, do the HLAs come easily out of the head?

Thanks.

Michael

[Infinitiguy19]

Have you tried Luboro moly (Liqui moly) engine flush? One of the FGY33 guys on here says it worked for him. I plan on doing that myself (Crappy oil, Good filter and Lubro moly for 15-20 min idling or very light driving. Then change to good oil and filter.

Other than that the only way to bleed the HLA's is to remove them from the engine. Are the rockers loose? How do you know its a HLA noise?

[Q451990]

I seem to remember someone (or the FSM) mentioning that the head needs to be heated to remove the HLAs?

Heath

[mpaton2]

I seem to remember someone (or the FSM) mentioning that the head needs to be heated to remove the HLAs?

Heath

I remember that also, quite possibly from the days back around 2000 when I bought this car, and was on the Yahoo forum.

But since then I bought the FSM, and it doesn't mention this (or I missed it).

Since then my searches have brought up some posts about disassembling and degunking the HLAs, but I haven't turned up anything about removing them.

Michael

[cientortas]

I've had HLA tick on my 94Q for a couple of years...right after I switched from conventional to synthetic oil. I'm assuming something got dislodged and plugged up the HLA oil passage. Nothing I've tried has helped...including different weight oils, both conventional and syn, Marvel Mystery Oil, Rislone, BG engine flush, etc. I might try the Lubro Moly thing.

Cams have to be removed...if you do it according to the FSM. I don't see how you could get them out without removing cams.

[mpaton2]

Cams have to be removed...if you do it according to the FSM. I don't see how you could get them out without removing cams.

Like many FSMs, it isn't trying to tell you how to replace the HLAs, it's telling you how to strip down the engine.
So it seems it may well be possible without removing cams.

Are the people who posted on cleaning HLAs still on this forum?

Michael

[3Q Jay]

I'm preparing myself to change or clean out some HLAs on my 1995 Q45. The ticking of 4 or 5 of them is testing my mechanical sympathy to the limit. I've seen articles on cleaning them, but my question is really about removing them.

Is it possible to position the crank to a point where the piston is down the bore and the cam for that lifter is not pressing on the follower, and then use a suitable tool to push the valve far enough through the guide so that the follower can be lifted off the HLA, and then the follower and HLA can be removed?

I understand that "a suitable tool" probably won't be some pry bar lying around.

Or must the cams be removed?

In either case, do the HLAs come easily out of the head?

Thanks.

Michael

Interesting idea that i hadn't thought of. how would you simultaneously push the valve down far enough and remove the roller/follower from the tip end of the valve stem? do you know which HLA's are in question? if near the back might be able to loosen the cam bearing caps and 'tilt' the cams up. if you do loosen the caps, be sure to 'drift' the tool into the special screws. you won't get a second chance if corners start to round.
as for your question on removing HLA from the head i think it all depends: how much varnish? how tight are the o-rings? speaking of o-rings: those are not sold separately from nissan. i sourced some very thin viton o-rings that may do the job (i haven't mustered up the courage to tackle pulling the HLAs though.....).
if you go a head with this, please take lots of photos for us mortals.