Camshaft Plug replacement

[RON98]

doing one for a customer along with TB install and started taking pictures 1/2 way through. had some one ask about cam plug replacement a while ago on prime but no one had any pictures besides Honda manual.

There is not much in the NSX manual about this cam plug replacement.

Its the same as camshaft removal.

pictures are kind of rough since I was slipping and sliding with oily gloves on my camera.

im starting with the camshaft pulled off. when you take off the camshaft, follow the cam holder bolt removal sequence. work from the center out.

====================================================
Yes, these suckers leak all the time. The leak is not usually bad, but its enough to bug you. As you can see from this picture, the oil has worked all the way through the gasket maker and also the cam plug itself.

Picture shows the cam plug location in the front head.

cam plug location in the rear head. I marked out the old gasket maker material that will need to be removed with a gasket scrapper or an razor
Make sure to get 100% of this stuff off or there will be leaks again due to an uneven sealing surface.

After its been cleaned and old gasket maker scrapped off, SPRAY with brake fluid to remove oil. now surface is prepped for the new gasket maker

This picture is of the top half of the camshaft holder which mates to the top of the cam plug. There will also be old gasket maker stuck to this part. make sure to clean it off with razor then SPRAY IT with break cleaner to remove any oil.

Picture of the Camshaft seal. This is the opposing seal which prevents the oil from leaking out the front of the camshaft. To get it off you must remove the cam gears.

Pull the camshaft and camgears out in one piece. The manual will tell you to take off the cam gears before losening the cam holders... its PAIN! dont do it.

Once you have the camshaft and cam gears off as one piece. the magic trick is use an impact gun. You dont even need a vice, you can hold the camshaft in your hand and just power it off with the impact easily. Otherwise, taking off the cam gear is a nightmare. :wink:

Sexy hand :biggrin:

Old and ugly.

New and clean. Make sure to lube the camshaft with motor oil (10w30) first before sliding on the camshaft seals. The oil will prevent the new seal from ripping or getting scored. When you install the cam seals, make sure the spring is facing in, also when you place the camseals on the camshaft, the sealing surface tend to get folded over.... so make sure everything is flush and sitting properly.

Now its time for gasket maker. I use the good stuff by pematax. It's great and seals forever. I prefer it over the Honda stuff, remains flexible, soft, great with high temp and its also very resistant to oil and other liquids. The key here is make sure the gasket maker (GM) surface is clean of oil. GM bonds with both surfaces so there must be no oil on the cam plug or the mating surface on the camshaft holder and the head.

Be generous but not liberal with the gasket maker. A thin layer will do just fine. Be sure to over lap and cover the flat portion of the head and also the cam holder as shown in the picture.

gasket maker on the head side.

Cam holder in place over the new cam plugs 4, 3, 2 are in place and cam holder 1 not there yet. For the camshaft seal, make sure the sealing surface does not have oil on it and should be dry.

this is a big job and although the plug is only $4-5 each, the cost to get to these puppies are extensive. I recommend you do these during your timing belt job if your cam plugs are leaking. if you need to replace these down the line.... its basically a TB job and then some (depending on the mechanic). For the diy its a pretty big job and I advise everyone to look through the manual first before attempting. I think someone can do this job with out pulling the tb but its very tricky on a dohc v6 engine where you have to isolate 4 cam gears and to make sure the tb does not skip a tooth. If it does, you have to align the TB from scrach. High skilled to do it with out pulling the timing belt.

If anyone want to under take this task with out pulling the TB, let me know, maybe we can see if this option is worth the risk and "time savings".

if you have any questions about camshaft plug, seal or anything else, please feel free to contact me through pm or email.

Warm regards and happy motoring

Rob:smile:

 

[RON98]

lol just thought of something.

maybe you can just pull the camshaft holder #4 and get directly to the cam plugs! :biggrin:

with that said, the camshaft does protrude into the cam plugs, clearance issues?. :biggrin:

well regardless, someone's gota try it. nsx is all sealed up so im not taking her apart again :tongue:

 

[goldNSX]

Thanks very much, Rob! Is there any chance that you move to Europe sometime in the future?

I believe that it was me who asked about these cam plugs here. The parts are ready to install and we do it with the TB on deylos car in march first. (From my point of view it's better to ruin his engine first than mine :tongue:) Anyway, we'll remove the complete engine (I know it's no real need but we try to avoid the chiropracticant). Within the TB job, how long does it take in practice if we've read the manual first?
In which order do you torque the cam holders. The manual only shows black points (as a result of the pdf conversion?).

 

[NSXBill2]

Good pics and instructions/commentary. I always wondered what was involved. Sure hope I never have to do it. :biggrin:

How could you possibly do it without lifting the cam out of its seat...which means removing the cams and thus the TB?

 

[RON98]

Hi Rob,

You must lift the cam about 1/2" to get the cam plugs out, so if you loosen all the bolts from each cam holder the cam will lift under pressure of the cam followers.

In your pic the cam plugs have Hondabond on them, which means they have been replaced already and WHY they are leaking. They should go on dry, just like the oil pan gasket.

Regards,
LarryB

Here is another way, thanks to the ingenuity of Larry Bastanza. 2 heads are better than one:smile:

If you dont need or want to change your front camshaft seals. this way is definitely quicker since you dont need to pull the camshafts. Im guessing its about 1 hour faster.

However, if you wanted to change your front camshaft seals, im sure pulling the cam with the cam gear and hitting it with the impact "gun" :wink: is faster and easier.

In regards to the Hondabond and the cam plugs leaking. Personally I always used the good stuff and had no issues as of yet. Just could not believe those 3 little ribs can keep the oil at bay. I'll try it dry next time.:smile:

Regards

Rob:smile:

 

[RON98]

Thanks very much, Rob! Is there any chance that you move to Europe sometime in the future?

I believe that it was me who asked about these cam plugs here. The parts are ready to install and we do it with the TB on deylos car in march first. (From my point of view it's better to ruin his engine first than mine :tongue:) Anyway, we'll remove the complete engine (I know it's no real need but we try to avoid the chiropracticant). Within the TB job, how long does it take in practice if we've read the manual first?
In which order do you torque the cam holders. The manual only shows black points (as a result of the pdf conversion?).

(From my point of view it's better to ruin his engine first than mine :tongue:) :biggrin: :biggrin: :biggrin: always a good friend eh!:tongue:

in regards to the cam holders. start from the either cam holder 2 or 3 in the middle.

start with the bolts closes to the middle of the engine and make an X pattern out always hitting the next setup of bolts closes to the center of the head.

..5........7
9...1...3...11
.......S<--- center spark plug hole so either cylinder 2 or 5
10..2...4...12
..6.........8

tb is very easy with the engine in. its all about shifting the engine up and down to access the parts you need to reach.

pulling the engine is a good idea if you wanted to go to town on it and change every seal and clean every nook.

For just the TB, from my point of view and keeping prices good for everyone, there is no need to pull the engine and no need to charge for extra labor that does not need to be done.

The time required differes. im sure me and larry can both say that it took us a lot longer our first time then it did now. Also along the way you work out tricks to make the job easier and faster. If you put togeather a computer the first time, it might take a long time.. the 100th time... you can do it with one eye closed.:wink:

good luck and if you need help, let me know.

Rob

 

[RON98]

Good pics and instructions/commentary. I always wondered what was involved. Sure hope I never have to do it. :biggrin:

How could you possibly do it without lifting the cam out of its seat...which means removing the cams and thus the TB?

I think if you do it Larry's method it might be possable. Zip tie the timing belt to the timing gear. At least 2-3 zip ties/gear to prevent the belt from skipping a teeth.

Then loosen the cam holders, get that 1/2 of space and then once your done use the tq on cam holder bolts to pull the cam back into position since there is tension on the TB.

im not sure how the TB will react but there is always a solution.:wink:

 

[The Kid]

Great write up Rob. I had bought the fancy covers from SOS when they were just released but had just done my T/Belt-Water pump weeks before and didnt feel like it was worth the hassle. Very informative:wink:

 

[Daedalus]

Great info--thank you.

I'm wondering if removing the plugs without replacing the front cam seals would encourage the seals to leak? Seems the movement of the cams might upset the seals if they're old and less pliable than new. Thoughts on this?

 

[RON98]

Great info--thank you.

I'm wondering if removing the plugs without replacing the front cam seals would encourage the seals to leak? Seems the movement of the cams might upset the seals if they're old and less pliable than new. Thoughts on this?

On the cam seals, the outside ring is soild and has no flex. the internal seal ring is pretty soft so that can move around. When you loosen up the cam holders, the preassure from the cam seal is also released and so they will be able to move around.

If you doing a TB, i dont see any reason why not take the extra hour and get both seals done.

However, if your just doing the cam plugs and if you can get away using L's method of 1/2 clearance and not pulling the TB off, then its definit time saver.

 

[enkrypt3d]

wow its kinda heart breaking to see my baby in pieces like that!

I can't wait to get her back on the road man omg...... :tongue:

 

[nsx24]

I did the rear set of cam plugs a year ago using the Larry B way and it worked just fine. I loosened the cam plates a little at a time and eventually you could get a screw driver and pop out the old. It was a little trickier to put back in as you dont want to wipe the Honda bond off forcing it back in. Just know, it can be done without removing the TB, and cams.

 

[Larry Bastanza]

It was a little trickier to put back in as you dont want to wipe the Honda bond off forcing it back in.

Again, there should be no Hondabond used. Two reasons:

1. The service manual does not call for it.
2. I have NEVER taken a factory fresh NSX engine apart that had Hondabond on them.

If the factory does not do it, it is a pretty good bet it is the correct way.

I have seen Hondabond actually act like a lubricant, typically on oil pan gaskets, and the Hondabonded area is what was leaking. I always install them completely dry.

That's my story, and I am sticking to it

Regards,
LarryB

 

[RON98]

Again, there should be no Hondabond used. Two reasons:

1. The service manual does not call for it.
2. I have NEVER taken a factory fresh NSX engine apart that had Hondabond on them.

If the factory does not do it, it is a pretty good bet it is the correct way.

I have seen Hondabond actually act like a lubricant, typically on oil pan gaskets, and the Hondabonded area is what was leaking. I always install them completely dry.

That's my story, and I am sticking to it

Regards,
LarryB

hey Larry

it was weird.

i was just looking at another customers car couple of days ago. It was Mike's 95 Targa Purple exactly like Corey's. Same Honda bond in the plug seals.

I always remembered Honda Bond on the cam plugs. I never use honda bond. I use "the good stuff stuff". When we pulled my buddies oil pan off, we took off all the bolts and this stuff was holding the oil pan on there like we had still left bolts in. This is why i choose this stuff over honda bond anyday.:wink:

Also i use it on valve covers all the time and it seals real tight and clean.

I got two nsx. ill check tomorrow.

Regardless, with or with out. As long as we get to the same results of no leaks

Happy motoring!

Rob:smile:

 

[L8apex32]

When you are doing the timing belt, it is pretty easy work to replace the cam plugs. One thing not mentiond above, but in the manual is to loosen the valve adjust nuts, then unscrew the tappets all the way [they have a positive stop at the end]. Also, the cam holders want to come straight up and out because they have tight dowl pins - just take them all the way off - they are labeled for replacement. Now you can easily lift the cam and replace the plugs. Then, remove the cam gear to get to the cam seal.

I did mind during a TB replacement so I already had the timing belt off. Very easy to replace the cam plugs and seals at this time. In my case, none of the seals were leaking, just one of the plugs.

 

[goldNSX]

How long did it take you to do the cam seals?

 

[L8apex32]

Well, considering that the timing belt was already taken off, it was easy to take the cams out. I loosened all the valve tappets and backed off the screws by hand. Then loosened all the cam holder bolts by hand, then started taking them out by hand. That was tedious so I switched to the air ratchet. Then, I was careful taking out the cam holders since I hadn't done it before. When I found out they were just fitted to the dowls, I took each one out successively faster. And, each is labeled (F1, F2, etc) and once I noticed that I was sure I'd get them back on in order. I'd say I spent 45 minutes taking the front cam holders and cams out, which necessarily takes the cam plugs out. I spent a few minutes cleaning the cam plug fitting in the head (one had gunk in it). For the rear, I'll probably get the cams out in 10 minutes.

I have not taken my cam gears off yet - but I have an impact gun so I know it will be quick. It looks like there is only the gear, the gear alignment pin thing (forget the name), the cam and the seal. I expect the seal to slide off (once the gear is off) and the new one to slide on. Minutes more is my guess.

Re-assembly appears to be straight forward.

I brought this up because I expected the springs on the valves to push up and against the cam and that to cause complications. That's not the case.

One more thing - I had my cam pins in (drill bits in my case) and when I started to loosen the valve tappets, I then realized I wouldn't need the cam pins any more. But, one was stuck pretty tight due to changing force on the cam from the valve springs, lobes, loosened tappets, etc. I had to spin the cam a little with a wrench on the nut to get one of them out. If you are going to move, adjust or remove the cams, cam gears or cam plugs, you should take cam pins out first. The manual shows how to align the cams for re-installing the timing belt, which includes re-installing the pins. Plus, I follwed the suggestion from this thread to mark my belt and the cam teeth as an extra precaution.

I'll report back here if anything comes up replacing the cam seals - but it looks trivial at this point.

 

[L8apex32]

Ok, reporting back (see previous post). Even though taking the cam holders off, cleaning things up, swapping plugs and seals, and putting it back *could* be quick, I found a way to jack it up a few ways.

One way I jacked it up was to put the cams back on, tighten everything down, and THEN check the orientation of the cams. Once tightened down, rotating the cams may cause a valve to hit a piston. Actually, there is no "may" about it if you keep moving the cams or the crank if not in sync. So, I had to take one side off to re-align the cam before tightening down again.

The next thing I did was read the manual for sections that I had been reading out of a good how-to from this site. My how-to didn't talk about cam plug replacement. The shop manual said to use gasket maker (Hondabond) near the cam plugs. Oops. This makes the 2nd time I took the cam holders off, re-cleaned stuff, then re-assembled.

(If you don't have an air wratched, this will take forever!)

So, things were good. I then put the timing belt on, and after a lot of checking and re-checking why it wasn't fitting, it went on. Ta-da. I then carefully followed the tensioning procedure and, while using just a little force to tighten the front side intake cam, something slipped. I thought it might be my wratchet between positions so I tried again, this time more carefully. This time I noticed the cam teeth slip. CRAP. I went in to have lunch but didn't come up with any sure-fire way to ensure exactly where the cam should be relative to the crank. (I had rotated the crank the 9 teeth or so, until the blue line on the pulley is up so I had to take both sides apart to get all to #1TDC.) So, this makes the 3rd time I took the cams off, re-aligned to #1TDC, and re-assembled (and re-torqued) the 40+ bolts. [At least it was easier to put the TB back on this time, with all this practice.]

So, yeah, its real quick to just take the cam plugs out and seals and put it all back together.

 

[enkrypt3d]

aww the pics are gone

 

[RON98]

aww the pics are gone

Hosting service is moving server.

i only had time to move some mission critical stuff to avoid down time. the pictures will be back up in 48 hours.

warm regards

Rob:smile:

 

[NSXknight]

Hi rob

I read a good shop should be able to replace cam seals in about 3 hours? My case is that the TB and WP was already done last year so wouldn't need this and supposedly all the seals were also done but if it is the cam seals leaking than this isn't the case.

This is related to my other thread if it is the cam seals that are leaking.

Hosting service is moving server.

i only had time to move some mission critical stuff to avoid down time. the pictures will be back up in 48 hours.

warm regards

Rob:smile:

 

[L8apex32]

Hi rob

I read a good shop should be able to replace cam seals in about 3 hours? My case is that the TB and WP was already done last year so wouldn't need this and supposedly all the seals were also done but if it is the cam seals leaking than this isn't the case.

This is related to my other thread if it is the cam seals that are leaking.

I'm not sure about replacing the cam seals in 3 hours. You need to remove the cam gears to get the seals out. This means you'll be taking the TB off, then putting it back on. That means taking the alt and A/C belts off, brackets, TB covers, etc. A TB is not a 3 hour job.

I don't know and can't imagine off hand how you could take the cams out without having to do all the TB R&R work.

If it was just the cam plugs, this would be different.

Again, I'm not too creative and necessity is the mother of invention. Maybe a more experienced mechanic will have a different opinion.

 

[RON98]

wow:biggrin:

never said anything about 3 hours. did i? if i did, i was not in my right mind. :tongue:

if someone just need cam plugs replaced and nothing else, im not sure how long its going to take. I can walk through it in my head but it always take longer since something always comes up and a perfect in head walk through to actural mechanic repair transfer is rare.

 

[NSXknight]

I was scanning a few threads and saw a time frame of 3 hours or so? Maybe it was 5? I don't know :biggrin: I hope cams isn't the issue on my oil leak We will find out next week!

wow:biggrin:

never said anything about 3 hours. did i? if i did, i was not in my right mind. :tongue:

if someone just need cam plugs replaced and nothing else, im not sure how long its going to take. I can walk through it in my head but it always take longer since something always comes up and a perfect in head walk through to actural mechanic repair transfer is rare.

 

[nikey22]

sorry about this dumb question... but what is the difference between a cam-seal and a cam-plug?

thanks!
I'm a newbie, please be kind!