When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
HELP! Stuck camshaft bearing cap prevents me from replacing camshaft housing plug.
Hello, Lexusarians
I am new to this forum. Reading your posts helped me a lot in the past.
I have a 1st Generation LS400 1990 with approximately 300,000 miles and counting.
I am currently replacing valve cover gaskets as there was a lot of grime all around it for a few years now.
LH (driver’s side) VALVE COVER is currently off the CYLINDER HEAD.
MY PROBLEM:
I plan to remove and replace CAMSHAFT HOUSING PLUG, which is located in the rear on the firewall side of cylinder head. The plug is covered with BEARING CAP labeled I6. Bearing cap is held with 2 bolts.
I removed those two bolts and thought I would be able to pick the bearing cap up to gain access to the rear CAMSHAFT HOUSING PLUG.
Unfortunately for some reason the BEARING CAP seems stuck. I don’t want to use too much force on aluminum and am hesitant using metal tools to pry the bearing cap off.
One try was to insert the bolts into the holes using them to wiggle the cap off, but it didn't wiggle out at all...
I'm thinking of some kind of a spreader? but the space is limited and I cannot seem to find a proper tool.
Do you have any suggestions? What should I do? Not too much space there.
Regards and thanks!
Below are some pics.
By the way: I also removed HALF MOON PLUGS made of metal sitting flush on the cylinder head surface edge. Space filled by one of them is visible on some pics.
Interesting tip which helped me remove those HALF MOONS: take a piece of wood like a short wooden stick, place it on one side of half moon and then hit the piece of wood gently with a hammer/rubber mallet so the half moon breaks the seal and starts moving in a round fashion. Once it has moved a bit you can take it out with your hand.
Last edited by Magda; 06-17-15 at 04:51 PM.
Reason: additional info, including part numbers
It's stuck because it was set in place with FIPG ( fixed in place gasket ) I had a heck of a time removing the front bearing cap on mine. I just kept lightly tapping it with a rubber mallet until it broke free. It was a little nerve wracking though. I ended up leaving those rear plugs alone since they clearly were not leaking.
By the way, I assume you were removing front cam bearing cap to replace camshaft seal. Did you have to remove distributor and timing belt for this job?
I don't think I'm going to do that now, but was wondering if one has to remove valve covers again to do the front bearing cap FIPG and CAM SEAL. I'm talking about pre-1997 LS400.
Thanks for your contribution.
You don't have to remove the valve covers for pre-98 models but you do have to remove the timing belt. On the 98 and up model the cams have to come out to change the cam seal. Your welcome.
HELP! Stuck camshaft bearing cap prevents me from replacing camshaft housing plug.
I managed to remove the rear bearing cap by placing wooden stick on the bearing and tapping wooden stick with a hammer / mallet. I tried to be gentle. It helped to tap the front edge of the bearing directing the tapping towards the rear / firewall... I tried to be gentle. I first tapped on the sides with bolt holes but it didn't seem to work...
I'm not planning to do the timing belt now thus cam seals will have to wait.
Should I attempt to remove the front cam bearing caps (=the ones close to the timing belt) and reseal with FIPG, even though I'm not doing the cam seals? Valve covers are out and I want to reseal with FIPG as much as possible without doing any damage. The Repair guide says that RH I6 front bearing cap determines the thrust portion of the camshaft. The same applies for LH I1 front bearing cap. Would I change the thrust while resealing them? Any ideas?
PROGRESS UPDATE on replacing CAM PLUGS:
The valve covers are currently off on LH (driver) and RH (passenger) sides...
LH valve cover was relatively easy to remove.
RH valve cover was a pain to remove due to a huge wiring harness running above the entire rear of passenger side cylinder/valve covers. --> Any tips on that? I'm worried that it will be difficult to put RH valve cover with a new gasket back in smoothly, without messing up the gasket placement. This wire bracket is huge and wrapped with old, cracked, peeling off remnants of what was an electrical tape 25 years ago... Some of it will definitely end up falling into the exposed cylinder head...
My Lexus LS400 1990 has stupid METAL BRACKETS behind cam housing plugs on LH and RH sides where the space is really tight...
On LH side it is held by one very inconveniently located 10mm bolt. I managed to get it off in order to have more space to play with cam bearing and its 2x10mm bolts. At this point LH cam bearing is off as well, like I previously reported.
However, on RH side the metal bracket , which blocks 2x10mm cam bearing cap bolts is held by 2 bolts in the back of cylinder head facing firewall, both bolts for this bracket seem impossible to unscrew... especially one of them. Also RH wiring harness does not make things any easier...
--> Does anyone have any idea what to do to unscrew this stupid RH bracket behind rear cam housing plug?
I really want to replace both plugs... but I may be unable to. It is not the end of the world. I can live with oil leaks... But I decided to do valve cover gaskets and cam plug to eliminate them...
Maybe no one knows how to replace RH cam plug because it is an impossible task thus no one does it. lol!!!!
I put plastic wrap over exposed cylinder head and over wire brackets to reduce the danger of contamination for whatever is exposed while valve covers are out.
Here are some pics of inaccessible wire bracket blocking access to bolts of cam bearing cap on RH side (passenger).
Inaccessibility is the reason why pictures are not that great.
Hi again,
I do this job slowly as I have other things in life apart from car repairs so please, bear with me! LOL
I have bent the RH metal bracket. Then I removed the bearing cap and its plug.
I am now ready to reinstall rear camshaft housing plugs on LH and RH sides. I removed old FIPG (which was milky/yellowish) in color) cleaned surfaces with alcohol.The only doubt is that the rear camshaft housing plug (metal plug covered with rubber) is a bit bigger than the space I'm putting it in. I tried to push it down in its slot in the end of cylinder head, but it feels like it does not go all the way through. I don't want to use FIPG on the plug as the manual/protocol does not mention it at all. I even found on some other forum that the plug should not be sealed with FIPG. However, some people use FIPG on the plug itself...
I plan to put rear cam plug in its spot on cylinder head even though it will not be pushed all the way. Then I will put FIPG only in proper place on cam bearing cap surface that meets cylinder head. I will then put bearing cap on top of cylinder head and a plug. I hope torquing the 2x10mm bolts on bearing cap will push the PLUG in so that it creates a proper seal...
Let me know if my thinking here is correct. There is not a lot of info on the plug in terms of proper installation technique.
Cleaned halfmoon plugs, rear cam bearing caps and bolts.
New sparkplug seals
Installation of new sparkplug seals (I already installed it and bent the metal tab back... so this is just a demonstration of my technique)
Adjusting new sparkplug seals so that they sit flush. This is also a way to remove them (just make sure that the metal tabs on the reverse are bent out of the way)
Rear plug in the background, ready for installation.
06-17-15, 03:33 PM
HELP! Stuck camshaft bearing cap prevents me from replacing camshaft housing plug.
