Valve clearance problem help

[Max666]

Hi All

so I decided to do some maintenance on the sons Ke70 with a 4k in it, and I had a go at the valve clearance, according to the manual I have are correct,

intake 0.20

exhaust 0.30

but when I put everything back together, I now have a loud taping from under the rocker cover.

i must have adjusted something incorrectly (no: 3 cylinder I think)

i may not have turned the motor 360” to do the valve clearance, on that one, just can’t remember.

any help would be appreciated.

And if I drive it, will I damage anything? 

( I’m not my sons favourite at the moment) 

cheers Max 

Edited October 28, 2017 by Max666
Forgot something

[ke70dave]

The only way to ensure you fix it propely is to go through the procedure for them all and re check them all. On a 4k it doesnt get any easier. 

My dad always taught me to adjust in pairs. 1 and 4 are a pair, and 2 and 3 are pair. 

When #4 is "on the rock", ie exhaust valve just closing and intake valve is just opening, #1 can be adjusted.

When #4 on the rock, adjust number 1. 

When #3 on the rock, adjust number 2

When #2 on the rock, adjust number 3. 

With this method there is no counting revolutions or any counting bullshit. Just keep spinning the engine watching the valves go up and down. And of you miss it, just keep spinning the engine by hand and go around again. Removing the plugs will make life easier but its a tiny engine you dont have much compression to deal with anyway. 

[Max666]

Thanks for the information, I’ll give it a go tomorrow. I think what I did was I didn’t do a full revolution to TDC after adjusting  cyclinder 2 .

hope I making sense 

cheers max666

[Max666]

6 minutes ago, Max666 said:

 

 

[parrot]

Take the plugs out and start again, and make sure the clearances are tight.

 

[Max666]

Hi 

yeah I did all the process correct except the revolution on cycinder 3 to tbc and I think I loosed the lock nut and did something to the rocker arm ....

[Max666]

Hi All just an update on my valve clearance problem.

i started from scratch and adjusted all the intake and exhaust clearances , put everything back together and to my frustration I still have the loud tapping noise.

i noticed that one of the rocker arms was very loose if that makes a difference to anyone.....

thanks again 

[altezzaclub]

Quote

one of the rocker arms was very loose if that makes a difference to anyone.

It does to the tappet gap...

Can you check that one and get it down to the correct gap??  Any slop in the rocker pivot on the rocker shaft.

The rocker face at the tappet gap will wear to suit the valve top, so you will get a cut-out forming on the rocker face. The feeler gauge will bridge that gap, so although you measure 8thou, the gap to the valve stem might be 12thou. 

In the past we've used a wire of the right diameter, or set them on the cam timing with a protractor.   .. or set it down a few thou and see if it shuts up!

Failing that, maybe its something else entirely.  Can you isolate it with a screwdriver on your ear?

 

[Max666]

Thanks for your reply and information.

i had a chance to do it over this afternoon with no distractions and I gapped the valves really close, and to my relief it ran like a new one. So one again, thankyou corolla gurus for the input .

cheers Max666

[rebuilder86]

justvreading this now. max those clearance  figures are for a hot engine. 

u must heat the engine up completely byvtaking it for a lolght 10 minute drive before pulling the cover off and quickly setting the gaps. 

personally, i just turn the engine over watching the valves and wait for the intake valve to close then i know both valves will be at there most closed cam position.

[Banjo]

Quote

The rocker face at the tappet gap will wear to suit the valve top, so you will get a cut-out forming on the rocker face.

Altezzaclub is perfectly right.   Unless the rocker arms have been ground, then, any of our olde Rollas with lots of klms on it, will have "gaps" worn into the mating surface of the rocker arms. 

The rocker arms are softer, than the valve stem, so will always wear first.  They are also bigger in area, so it will always wear a groove or gap into the rocker arm.

There is only one way to fix this permanently, and it is not that hard, or time consuming, and can be done DIY at home.

1.Remove the complete rocker sharft assembly & mounts.

2. Dissemble rocker shaft carefully, and lay all removed components out on a large piece of clean newspaper or the like, so it can be reassembled in the same order.

3.Wash each rocker arm.

4.Using a fine linisher, or a fine rotary grinding stone in your drill in a vice, carefully & gently grind the rocker mating surface until the wear groove or gap has been removed. Use both hands to hold the rocker, & use a curved action, as you pass the rocker surface over the wheel or linisher surface, to follow the curvature. Finish by hand on an oil stone if you are fastidious.

5. Reassemble rocker shaft; refit to head & regap each valve in your preferred manner to the factory settings.  The manual gives hot & cold setting gaps.

6. Take your Rolla for a run for 30 minutes; then check all gaps again with hot gap feeler setting after run. Adjust any that are out slightly.

7. Result: your tappet noise will be eliminated & the engine will sound like a new one; all other things being equal.

Cheers Banjo  

Edited October 31, 2017 by Banjo

[Max666]

Hi Banjo

thanks for all your input, even though that’s all above my skill level at the moment, you made it sound very interesting and doable in the future.

thanks again

Cheers Max