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Setting valves cold....

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Now that my engine is doubling as a coffee table in my garage, I thought, "what a fine time to set my valves". What are the down sides to adjusting valves on an ice-cold engine (actually, room temperature)? I always believed, perhaps erroneously, that one needed to warm up the engine to set the valves properly. After todays disaster with the dissolving paint on my new floorboards, I need some easy, gratifying project. I don't have the tranny on, I can pull the plugs, and the giant nut on the front end of my crank (no fan extension) will make this a picnic. I need a picnic. And a beer, but I won't.
 
Bill, the downside to doing the valves on a cold engine is that you have to "guesstimate" the thermal expansion in the valve train. On a fresh build and initial setting, I usually set them about .0015"~.002" looser than the hot setting. This puts me in the ball park, but if the specification calls for a hot setting, that's the only way to do it accurately.
Jeff
 
Andrew Mace said:
FWIW, most all Triumphs call for setting the valve clearance while the engine is cold.
Click to expand...


Whew! You made my day, Andrew. I think Bugeye is probably more attuned to racing setups.
 
But, Andrew, I believe that Bills cam card calls for a hot adjustment. I may be wrong, but all my performance cams are spec'd that way.
I also mentioned that <u>if</u> the adjustment was specified as a hot one, that was the way to do it. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Jeff
 
Dang, you are right. It is a Goodparts GP2 cam, set at 16/18.
Well, maybe I will just go through the exercise and check it. I kinda think one of my cylinders might be off, got a darker than normal plug. The other plug on the same carb is nice and tan.
 
Bill, if you set them cold, and then reset them hot, at least you will have established a baseline should the need arise to do them cold again.
Jeff
 
Bill, I saw that you have the more modern rocker arms on your engine. Any real advantage to doing those without a cam change?

I also was wondering if you have valve seals on your engine. I never used more than a quart of oil for 900-1000 miles until I added the additional oil line to the back of the head. Now I've cut that in half. I'm wondering if a small valve seal, similar to the old Chevy style would help.

I don't get smoke and the plugs are not fouled or discolored.
 
Hey Paul, the 1.55:1 roller rockers are ideal for the GP2 cam and the port/polish head; would essentially do nothing for a stock engine. Yes, I do have valve seals though there is some discussion about the advantage to them on a stock setup. My compression is up to 9.5 as you know.
 
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]FWIW, most all Triumphs call for setting the valve clearance while the engine is cold.[/QUOTE]

Bugeye58 said:
But, Andrew, I believe that Bills cam card calls for a hot adjustment. I may be wrong, but all my performance cams are spec'd that way.
I also mentioned that <u>if</u> the adjustment was specified as a hot one, that was the way to do it. /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
Jeff
Click to expand...

It is interesting trivia. The OEM spec is cold, but the spec for even the factory BL/JRT competition cams is hot. The card for the cam Reed ground for me specifies a clearance to be set when hot.


Regardless, the important point here is that people who have installed an electric fan don't have something to push & get *exaaaactly* right when setting the valve clearances.
whistle.gif


Unless they're with the jack-up-a-rear wheel crowd.
 
rotoflex said:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
Regardless, the important point here is that people who have installed an electric fan don't have something to push & get *exaaaactly* right when setting the valve clearances.
Click to expand...

This is where the starting handle comes in real handy-like.
 
Twosheds said:
rotoflex said:
<div class="ubbcode-block"><div class="ubbcode-header">Quote:]
Regardless, the important point here is that people who have installed an electric fan don't have something to push & get *exaaaactly* right when setting the valve clearances.
Click to expand...

This is where the starting handle comes in real handy-like.
Click to expand...

Actually, without the plugs and even loosening the alternator, the engine rolls over very nicely with a socket and long handled wrench atop that big bolt in the end of the crank that replaced my fan extension. And, you can fine tune the rock on the rocker with a little back-and-forth torque on the wrench.
Nothing to get in the way, can have a nice chair and cup of joe right by my side. With Lucinda Williams singing Essence
on my garage stereo.
 
Hey Bill,

Just curious about this hot/cold issue.

When I screwed up the dizzy install and had to
pull the valve cover gasket to find TDC, it
took me well over ten hours during two days to
adjust the valves.

How do you keep an engine hot for hours on end
while adjusting the valves?

just curious,

d
 
Tinster said:
How do you keep an engine hot for hours on end
while adjusting the valves?
Click to expand...

Don't do it in the winter, up North.

I can do mine in about 10 minutes, flat.
 
You do get better & faster at it with practice.

Also, if the clearances haven't gotten out, there's less to do. So the more often you do them, the less there's to do each time & the better you get at it.

I check the clearances when replacing plugs. Since the plugs need to come out to easily turn the engine, it makes sense to combine the operations.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]Nothing to get in the way, can have a nice chair and cup of joe right by my side.[/QUOTE]

Nothing beats GT6 & Spitfire owners for casual work on the engine, as they sit on the tire with a drink on the firewall shelf.

<div class="ubbcode-block"><div class="ubbcode-header">Quote:]This is where the starting handle comes in real handy-like.[/QUOTE]

Rub it in. Everybody envies the folks with a starting handle.
 
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