Adjusting mechanical valvetrain

[Dodge2004srt4]

I need to know the interval (Ive heard 6k miles) and the gaps for adjusting the lash. I also am not 100% sure in the procedure in doing this. I think you are supposed to move each cylinder to TDC to make the adjustments, and do it on a hot engine? Ive read on a performance cam listed that it was .006 for the intake and .009 for the exhaust? I think the cam in my engine is stock for mechanical valvetrain but even that Im not sure, it doesnt lope and engine vacuum is around 25-27in. Im used to performance cams, and not having to adjust valve lash.

 

Thanks!!!

Had my SQ for nearly 3 weeks, Ive tried searching with less than stellar results.

[The Rabbit1]

what year is yours? are you sure your valvetrain is mechanical and not hydraulic?

[Dodge2004srt4]

what year is yours? are you sure your valvetrain is mechanical and not hydraulic?

89, the seller told me it was mechanical, and its quite loud compared to a hydraulic setup in most cars. I think it needs adjusting, or soon will. It was a built motor, and was redone mechanical within the last 1000 miles.

 

Chris

[Indiana]

TDC then you can adjust the intake #1 and #2 and the exhaust #1 and #3 then turn crank one turn and then do the others. What you are doing is just making sure that those rocker arms you are adjusting at that time has the cam lobe for that rocker at its base. In other words, if the rocker arm it pushed down when you get to TDC on the intake #1 the first time, turn it one more turn OR just do the other 4 first.

 

If you have jet valves you do those the same way but you back them all off and adjust the intake valves FIRST then the jet valves. .010" for jet valves.

[Dodge2004srt4]

Has a Caravan head on it without the jet valves. Am I correct about the clearances for the intake and exhaust? Thanks, I wasnt sure about when to adjust each cylinder's valves. So its when they are on the base of the cam, easy to do!! Is the interval really so short? I know Honda's go like 30K miles between adjustments and I know some that dont even do them then......

 

Thanks,

Chris.

[The Rabbit1]

Has a Caravan head on it without the jet valves. Am I correct about the clearances for the intake and exhaust? Thanks, I wasnt sure about when to adjust each cylinder's valves. So its when they are on the base of the cam, easy to do!! Is the interval really so short? I know Honda's go like 30K miles between adjustments and I know some that dont even do them then......

 

Thanks,

Chris.

don't know where you heard that. have never seen a mechanical honda rocker. they are hydraulic and require no adjusting. The cam journals usually go before the adjustment, lol

[Indiana]

I got a Civic w/mechanical rocker arms.

 

http://hondacivicwor.../sohc-vtec.html

 

[/url]

 

http://2.bp.blogspot.com/_rLhH6OcF_gk/SgnJjfJpcUI/AAAAAAAAAcE/-qCvqUGUwRI/s1600/2199075_21_full.jpg

http://3.bp.blogspot.com/_rLhH6OcF_gk/SgnJqQ0yCvI/AAAAAAAAAcM/GVXAXubVZB4/s1600/d16y-vtec.jpg

Edited January 18, 2011 by Indiana

[The Rabbit1]

I got a Civic w/mechanical rocker arms.

I stand corrected, I forgot they have that. Now tell me that your "suggested service" includes rocker adjustments at 30K?

Edited January 19, 2011 by The Rabbit1

[Dodge2004srt4]

I stand corrected, I forgot they have that. Now tell me that your "suggested service" includes rocker adjustments at 30K?

What do you,... need to believe what I tell you in order to help me with a Conquest? Im looking for info, NOT a debate on servicing a Honda.

Ive known way too many people with Hondas and that's why I chose to stay with Mopar even if it is a DSM.

 

Now back to my thread and discussion, do you offer any real help or are you going to keep playing me as a fool?

 

So far youve asked me my year which I dont see as being important, and disputed having to adjust the lash on a VTEC D15. Single cam 1.5L

 

I really want to keep my car running and in good shape......oh, and Thanks!

Edited January 19, 2011 by Dodge2004srt4

[Dodge2004srt4]

Here you go Quoted directly from this website. http://www.s2000.org/articles/valve_adjustment/

 

A normal maintenance item for most Hondas that is often overlooked is the valve adjustment. Also known as setting “valve clearance” or “valve lash,” this adjustment is an important maintenance item to insure lengthy, proper, and efficient operation of your engine.

 

The valves in your engine open and close to allow intake air to flow into and exhaust gases to flow out of your engine. The method that Honda uses is a rocker/follower that rides on the cam lobe (with the crankshaft and timing belt/chain turning the cams) that actuate the valves. The cam has a "lump" for lift and a "base circle" for the duration of the engine rotation where the valve is closed. In order to insure that the valves close completely the "valve clearance" or "valve lash" is set so that there is a known clearance between the valves and the rocker arm.

 

The valve adjustment is important for two reasons. One, if the valves do not close all the way, you can lose a substantial amount of power since the intake mixture will be "squeezed out" during the compression cycle (hence less mixture burned, less energy resulting from combustion). This might also result in burned valves as the exhaust valves depend partly on contact with the valve seat (head) for cooling. Second, if the valves do not open all the way you will get poor flow through the head (less mixture) and again lose power.

 

As the engine ages and more miles are put on it, the valve clearance can change. Repeated thermal cycling of the mechanism as well as mechanical wear will alter the adjustment slightly, resulting (typically) in increased clearance. This increase in clearance is usually characterized by an increased “ticking” at idle. While Hondas generally run wide clearances and tick some at idle, if you notice a more pronounced ticking noise you should probably consider having this adjustment performed.

 

The normal service interval for the adjustment has changed wildly over the years. In the late 80’s, Honda recommended it every 15,000 miles. In the late 90’s Honda changed that interval to every 30k miles. Now, with the S2000, this has been changed to 90,000 miles.

The adjustment usually takes 1-2 hours on a typical Honda. Since the adjustment needs to be done with the engine cool, there is usually at least a 3-4 hour cooldown period that must preface the actual adjustment. Most dealers and service stations will only charge for the work done (and not the wait time) or simply charge a flat fee. Regardless, this is typically a job that costs in excess of $90 or $100.

 

Depending on the motor and the methodology, you may set this adjustment by measuring the clearance between the valve and rocker or the rocker and the cam. Since the two are related geometrically by the length of the rocker (and where it pivots, it is crucial that you know the clearance for your engine and where exactly to measure it. It is also crucial that you know what temperature the spec is at (100F for both the Prelude and S2000). The valves must be adjusted at near the same temperature, since as little as 30 or 40 degrees F will change the clearances.

 

This document is written with both the F20C (S2000 engine) and the H22A (Prelude engine) in mind. While the process is very similar, there are a few differences. These differences will be noted where applicable.

[The Rabbit1]

Had my SQ for nearly 3 weeks, Ive tried searching with less than stellar results.

 

seeing how you didn't download the FSM and get the specs from it, I was supposed to know you knew that newer models have hydraulic adjuster/lifters and do not require this maintenance? or whether or not you know your car has a mechanical setup?

 

Here's the link for the FSM:

http://www.starquestgarage.com/manuals/service/service_manual_index.html

 

Link to PSQ how to do's:

http://starquest.i-x.net/viewforum.php?f=12&sid=2e5c48a3892766e754736ba4dd238e7e

 

and link to insight on your new car:

http://www.starquestclub.com/forum/index.php?showtopic=66449

[The Rabbit1]

and here's another place you can find answers to the simplest of questions:

http://www.starquestclub.com/forum/index.php?showforum=27

[Dodge2004srt4]

and here's another place you can find answers to the simplest of questions:

http://www.starquestclub.com/forum/index.php?showforum=27

So you DO take me for an idiot.....

Thanks, please stop posting everything around the SIMPLE questions I asked which arent simple and mainstream. If you dont know the answers then troll another thread please.....

I have both of the 89 FSM's including the electrical, and KNOW FOR A FACT that I have a mechanical setup. I dont need to figure that out, and I dont need to know basic stuff. If this were basic then it would be in the FSM for an 89. The engine was built, and is not stock. I never said it was.

 

Please READ what I have been writing, Im asking for specs for my car knowing what I have but not knowing the interval or the clearance. The guy I bought it from doesnt know either, as he only put 1500 miles on it in 1.5 years. Someone on here should know the spec as Im sure Im not the only one using this setup.

 

Try a search on here for what MAFT to buy for our cars. Lots of info about them but not one person says to go with one from a 1st gen DSM. They sell vehicle specific ones and general ones. I searched myself blue trying to figure it out one weekend so I could buy one off craigslist with a 3in GM MAF for $100. Lost out cause searching on here is like trying to see behind your eyeballs, you end up finding everything around what you wanted.

[The Rabbit1]

I did read, and asked a simple question. If I asked how to adjust a centrifugal blower pulley and I just bought this car would you not ask why I asked a random question that might have nothing to do with my car?

 

I wonder why your having issues with a recently replaced head, maybe the noise isn't from the rockers. Have you adjusted them yet? are yous sure the noise is coming from up top?

[Shelby]

i don't realy like the turn to TDC and adj methoid,, i always go by fireing order and place each cam lobe at the lobes base ( lobe pointing down) then adjust that valve,,then turn engine with wrench and adj the next valve in fireing order ,, then do the same for the exh,,this only means turning the engine over two full turns,, but i normaly do a double check on all the valves

 

now some times even with proper lash you will have valve train noise this can be cause'd by useing solid rockers on a hyd cam ,if this is the case try droping the last .001"

 

an easy way i have to find the proper adj is to place feeler under the rocker and turn the screw untill the feller gauge can not move'd , now lock the adj nut,, after a few trys you'l find the proper tightness on the feller gauge arm .

locking the loc nut will pull the screw up a tinny bit ( do not over tighten the loc nut )

 

worn rocker arms or shafts can also effect the valve lash

[Dodge2004srt4]

I do need to know the proper lash though.....

[Dodge2004srt4]

I did read, and asked a simple question. If I asked how to adjust a centrifugal blower pulley and I just bought this car would you not ask why I asked a random question that might have nothing to do with my car?

 

I wonder why your having issues with a recently replaced head, maybe the noise isn't from the rockers. Have you adjusted them yet? are yous sure the noise is coming from up top?

If you said there was one on there I wouldnt ask unless I had reason to think you didnt know what your talking about.

I havent adjusted them because I havent gotten the answer I needed about the lash.

The motor was built and there have been no problems except excess noise. I dont think the person who built the motor knew the proper settings or its just noisy.

I need to know the spec before I can adjust them and come to the conclusion that adjusting them was all it needed. I have to assume they built the motor correctly. It runs great.

[Shelby]

hot

ink and jet .006"

exh .010

[The Rabbit1]

I have to assume they built the motor correctly.

No, you don't. This is what I was getting at. I have seen many an idiot throw a motor together with a Haynes manual. You missed my thread about my flexplate and transmission for my car when I got it. It ran fine, but the flexplate was held together with tack welds and the trans was missing parts internally. And it had a ticking sound, got it for next to nothing because they thought it was a rod bearing.

 

Never assume they did it right, jerry rigged setups work and sound just like the real thing ya know. for all you know the head was put together wrong and is causing the problem. You want to assume i'm the idiot and the person who put your car together was the knowledgable one. hell of a gamble.

Edited January 22, 2011 by The Rabbit1

[Dodge2004srt4]

No, you don't. This is what I was getting at. I have seen many an idiot throw a motor together with a Haynes manual. You missed my thread about my flexplate and transmission for my car when I got it. It ran fine, but the flexplate was held together with tack welds and the trans was missing parts internally. And it had a ticking sound, got it for next to nothing because they thought it was a rod bearing.

 

Never assume they did it right, jerry rigged setups work and sound just like the real thing ya know. for all you know the head was put together wrong and is causing the problem. You want to assume i'm the idiot and the person who put your car together was the knowledgable one. hell of a gamble.

The guy works on quests around here, so I dont think he would come recommended if he was just a shmuck with a Haynes. Ill start with the adjustment and work from there. Thats all I ever wanted to start with, then Ill go from there.

[Dodge2004srt4]

Update on this today:

I have the valve cover off to check the top end before I do a compression test. I have a missfire sounds like its mechanical. So Im checking the clearances and just a visual to make sure non of the springs are broken. The miss occurs throughout the RPM range and the car backfires through the exhaust and intake. I know it could be a timing issue but for now Im working with a hunch.

 

Now, I know I have a mechanically adjustable valvetrain setup seeing it with my own eyes. I also see shims installed on the cam lobes and under the rockers just between the valve stems. Im going to take a picture so everyone can see, and maybe comment on whats in there. I have no clue if its a regrind performance cam or a stock one reground to stock specs. Im trying to find that out now.

 

Since none of the springs look broken Im going to check the clearance and move on to a compression check.

 

Pics will come in a few hours max.

 

Thanks,

Chris.

[DzNutz]

Shims? Look forward to the pix.

 

Personally I have mine adjusted to .008 just to quite the sound a bit. Course I have a hydraulic cam with mech lifters too. Going to be doing a set of roller rockers with hydraulic lifters and a roller cam from Tim soon.

[Dodge2004srt4]

Ok so I adjusted everything and there is no more miss. They were way too tight. The noise is about the same which isnt loud per se but its not hydraulic quiet. Fun stuff and didnt take too long. Wish it wasnt 85 though. I put some descriptions below the pics.

http://i173.photobucket.com/albums/w75/dodge2004srt4/conquest%20head/DSC00708.jpg

OK maybe its part of the screw and not another shim, but it didnt look right to me.

http://i173.photobucket.com/albums/w75/dodge2004srt4/conquest%20head/DSC00707.jpg

Part of the rocker? I thought this may be a shim.....look right in the center of the pic where the cam lobe is.

http://i173.photobucket.com/albums/w75/dodge2004srt4/conquest%20head/DSC00709.jpg

No jet valves!! YAY!

http://i173.photobucket.com/albums/w75/dodge2004srt4/conquest%20head/DSC00710.jpg

Pic of whole top end.

 

Chris.

[Tim_C.]

Well, the cam end of the rocker is normal OEM. It is a curved slipper that is hardened and epoxied to the rocker. Thus the reason it looks like it could be a separate part or shim. This curved slipper facilitates a quick acting function to snap the valve open faster and hold it open longer. Whereas a roller rocker tip has a very narrow contact patch to act slower, but it can also facilitate a steeper lobe designed for the roller that is wider at the top for more flow at full lift.

 

It sounded like you were referring to lash caps on top of the valve. I can't see it well enough in the pic, but the size relationship between the adjustment screw tip, and the surface it is touching (be it a cap or valve tip), looks to me like it is the normal valve tip / top of stem. It doesn't look like a lash cap / shim, but again, I can't tell for sure from the pic. Lash caps are a way to help keep the rocker geometry correct when a reduced base circle performance cam is put in place of the stock cam. It basically keeps the relationship between the valve top and the rocker itself the same as OEM so the same adjustment screw can be used instead of using a longer one that moves the geometry of the rocker away from the valve top, which is less ideal than a short screw that keeps the rocker tip closer to the valve. However, most of us have learned that lash caps aren't really needed on just about any mechanical cam set-up on our cars unless it is a very radical grind for rpm above 6500. Caps will have a larger diameter than the valve stem, and will cup over the end of the valve. They are fairly obvious, so you should be able to see that they are considerably larger than the valve stem.

 

It is good to adjust the mechanical rockers a little tight. You actually get more performance, and it does quiet them a bit and the adjustment lasts longer. But only .001 - .002 tighter than stock. I go about .008 exhaust, and .006 intake.

[Indiana]

that doesn't look like a lash cap to me the stem and tip diameter appear the same.

 

http://i173.photobucket.com/albums/w75/dodge2004srt4/conquest%20head/DSC00708.jpg

 

 

This is a lash cap

http://www.b2600turbo.com/images/IM009406.JPG

 

this is a lash cap and elephant foot

http://www.b2600turbo.com/images/IM009434.JPG

 

without the cap on you can see the locks

http://www.b2600turbo.com/images/IM009452.JPG

 

cap over the tip with locks shown on stem

http://www.b2600turbo.com/images/IM009454.JPG

 

 

you can see the stem and cap diameter difference

http://www.b2600turbo.com/images/IM009501.JPG