Tappet Adjustment

[Dangil]

I wonder if someone can help me, i'm in the process of checking the clearance of the tappets. My query is about the right hand side intake rocker arm, its got a spring loaded timing plate pushing it down.

Do you adjust the clearance so you over come the pressure of the timing plate so the rocker arm touches the cam lobe base or do you adjust it, so its within spec without moving the timing plate?

The engine is an F18B2.

 

[AndyB1976]

Hi

Not entirely sure what you have going on there. I used the markings on the cam pulley to bring each cylinder to TDC then feel for the gap.

Does this image represent what you have?

 

[Dangil]

Hi mate, yes thats exactly the same as my engine. At the moment there's no movement on the r/h/s intake rocker arm as the timing plate is pushing down on the rocker arm. One of the small arms on the timing plate has snapped off which is why I think somethings wrong (I found the the bit that snapped off in the sump, god knows how long its been there). The other 3 arms are bent upwards (i've brought 4 new ones from Honda to compare).

I've had the car for about 6 years, I replaced the belts etc when I first got it but I've never touched the tappets.

I'm guessing someone at some point has adjusted them too tight which has fatigued the timing plate arm over time?

 

[AndyB1976]

The engine only runs on 4 intake valves (or 12valves if you include the exhaust) until VTEC then the left hand rocker arm engages bringing in the whole 16valves into operation. The cylinder is on the intake stroke hence the valve is depressed, using the cam pulley you can determine which cylinder is on what stroke, you want to bring each cylinder to Top Dead Center before feeling for the gap which might not need adjusted anyway.

If you have some photos it might help or allude to what might have gone on, I think if things were badly bent or floating around in the sump any issues may have manifested themselves before you took the rocker cover off.

I done a guide here, see if that is of any help...

http://typeaccord.co.uk/forum/topic/16845-diy-6th-gen-valve-clearance-howto/

 

[Dangil]

Thanks for the guide, i've adjusted tappets before so I know how to adjust them.





On a few American Honda forums they've had this happen but theres nothing about what caused it. The good thing is the part is too big to get in the oil pump.

 

[AndyB1976]

Interesting find, I wonder what that part does?

 

[exec]

Does that piece have a circle hole in the middle? Hav eyou ever run the car low on oil?

 

[Dangil]

No I keep it topped up. I think i've found whats wrong. I've taken the rockers off to replace the snapped timing plate & found the end of the spring has snapped off. I reckon because it was under no spring tension as the rocker has gone up & down the end of the timing plate has slipped out of the groove and snapped off when the rocker arm came up again.

Bad news is I need to try and find the end of the spring which means removing the sump again .

From what I can work out in the workshop manual, its just there to hold the small timing piston in place when theres no oil pressure from the vtec system pushing it out (I might be wrong).