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Dizzo7693
07-29-2003, 10:28 AM
I was curious... How can you tell if you have bent valves without taking off the head? I have pics of motor. How do I put them on the post??

2old_honda
07-29-2003, 12:00 PM
do a compression test

Chadroper
07-29-2003, 12:42 PM
Why do you think the valves are bent?

Dizzo7693
07-29-2003, 01:45 PM
Because of the fact that the timing belt broke off cause of wear and tear. And the car was tried to be started 3 or 4 times afterwards. I just took off the cams and the valves look straight.???

1988starter
07-29-2003, 06:38 PM
I would check your timing and make sure it is rignt

Blue Impact
07-29-2003, 11:12 PM
You should hear a banging or clanking sound if your valves are bent. It's hard for an airhead like me to explain, but if your valves really are bent, that means you're gonna need an engine transplant, a good way for a swap if you have the money to fund it. Good luck.

BootMachine
07-30-2003, 11:39 AM
Well...I know for a fact that the A20A engines are non-interference which means that the piston never will go in the same space as the valves so if your timing belt flew off nothing should have happened. UNless you have another engine.

If you realy wanna check....do the following!

- compression test...if not even...something is wrong
- listen....clacking at idle....valves may be bent or just lap needs adjusting

then:

- go and buy a 40$ head gasket
- take all the wires off the head and mark them with tape and a number so you know where they go...its easy...just take your time
- take off the valve cover and remove all the coolant lines
- unbolt the head
- pull it off
- take off the cam and the rocker assembly
- get a valve springs compressor
- remove the valves
- roll them on a glass coffee table and watch for a "WOBBLE"...if they do...they are bent..

I have a complete set of valves for the A20A 1.8L Bi-Carb engine if you need them!

pimp86LX
07-30-2003, 12:11 PM
idunno about that non-interference thing. I think i remember some threads of people blowing engines due to broken belts.....hmmm ill see if i can find them. (very well could be a different message board)

http://www.3geez.com/showthread.php?s=&threadid=19721&highlight=timing+belt+snap

http://www.3geez.com/showthread.php?s=&threadid=11046&highlight=noninterference

BootMachine
07-30-2003, 12:30 PM
hummm....

Well...I gues the only way to tell is to look inside...one time I put my engine back together and I had the wrong piston set to TDC so the valves were 180 degrees OFF...the engine cranked with no problem...I fixed the problem and the engine took off!

rocky2
07-30-2003, 02:30 PM
Take cam off. Now valves will be closed...Valve springs will hold all valves closed . Now put compressed air into spark plug hole.(made from old spark plug or store bought). listen on tail pipe/intake for air coming though....if none comes though...your cool..nada bent valves,do all cylinders. You could put a gauge and cutout cock and make a leak down test...see how long it holds pressure.

thundertank
07-30-2003, 03:34 PM
Like sean told me the a20a is not an interference engine. this happened to me a week ago and all i had to do was put a new belt on. the car runs just fine in fact better than it did before. so yeah the engine is not an interference engine youll be fine.



damn there are a lot of posts on this. i wonder how many people had to go through the hassle of taking their head off just to see that nothing is wrong. i also put my belt back on with the flywheel 180 degrees off. just make sure when you line it up the mark you go by is sort of a T. youll know what im talking about once you see it. trust me throw a belt on and youll be good.

someone should put this somewhere permanently so everybody knows. there are a lot of people that think it is an interference engine. ITS NOT!!!!

Dibbs
07-31-2003, 04:00 AM
I timed my car 180 deg off. I lined everything up where it was supposed to be 4 times and same result.....nothihg. Eventually, I just said screw it and rearranged my plug wires!:wtf:

Still works though!:flip:

infecto
08-01-2003, 09:24 AM
So whats it going to be interference or non? Someone know?

Sean
08-01-2003, 09:44 AM
thundertank already answered your question. non interference.

1988starter
08-01-2003, 10:12 AM
Originally posted by Sean
thundertank already answered your question. non interference.

Ive said it before and Ill say it again if sean says it's not it is not

BootMachine
08-01-2003, 11:01 AM
This is it.....official....

THE A20A Accord/Prelude engine IS NOT.......NOT....big fat NOT....an interference engine.

unless you shave your head...

POS carb
08-01-2003, 04:09 PM
what about valve float?

rocky2
08-02-2003, 05:40 AM
We are going to have to take a survey to see when there timing belts blew if there valves bent?

Sean
08-02-2003, 08:13 AM
valve float is a bit different becuase the valve can actually bounce off the cam lobe and really achive some serious lft. coupled with the fact that once your in valve float the spring is ossicalting so much that its tension is fairly low. so as i said vavle float is way different.

infecto
08-02-2003, 09:16 AM
Thanks for clearing that up Sean I just wanted to make sure as it seems everyone has there own opinion on the matter lol.

Dizzo7693
08-12-2003, 10:11 PM
Well just to let you guys know...I just got my head back from the machine shop and they told me I had 5 bent valves ( 3 Intake, 2 exhaust). So I guess it is interference. At least for my B20A5.

By the way since I knew I was going to have bent valve I thought I would just step it up a knoch with adding a 3 angel valve job, all brand new valves, chaved .0035 and just having the head cleaned up. Thought it would be nice to show the head some love. I also had to add a Bronze 4 puck stage 3 clutch, but having to use my stock pressure plate because of low funds.

Well thank you guys once again. And I beleive that this should be moved to somewhere permanent.:pimp:

mindlos
08-13-2003, 07:43 AM
I guess we assumed you had an A20

DBMaster
08-13-2003, 08:08 AM
Well, guys, there are a lot of shops out there making a lot of money saying that the engine is interference and that the timing belt needs to be changed every 60K miles.

All I know is that I worry a bit less now thanks to Sean and the rest. Thanks!

Vinny
08-13-2003, 11:10 AM
Originally posted by Dizzo7693
I was curious... How can you tell if you have bent valves without taking off the head? I have pics of motor. How do I put them on the post??

To get back to the original ??????? If you have air you can get a spark plug adapter and put air into the cylinder. Bring the piston for the cylinder that you are checking to top dead center which brings both valves closed (copmression stroke). If the air holds your valves are good (in theory) if the air pisses out, and your sure you are at "comression stroke" something is keeping the valve from seating all the way flush