Interference vs. Non-Interference engines

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Good morning folks,

Does anyone know of a website that I can go to and look up various vehicles and engines to determine if they are interference or not? I've been looking but no luck yet. Thanks! :thumbs:

posted by  cmeseadoin

Hmmm. Try Gates (as in belts). I seem to recall seeing that somewhere on there site.

posted by  vwhobo

I am so f*cking smart sometimes. Here is a chart listing interference engines that run belts. Good luck finding a truly comprehensive listing online.

http://www.gates.com/downloads/download2_common.cfm?file=TimingBeltReplaceP ages.pdf&folder=brochure&CFID=2502651&CFTOKEN=90780336

posted by  vwhobo

Here I go again. What exactly is a interference engine vs. non inteference ?

posted by  lectroid

Very simple grasshopper. An interference engine is one where the valves when open will touch the pistons at TDC such as when the camshaft timing is out of sync. This could occur if the timing belt or chain breaks, is incorrectly timed or someone is moving the cam or crank with the engine not fully assembled. Obviously a non-interference engine won't do this.

Keep in mind this is for a stock engine. Modifications such as changing the valve timing, valve lift or compression ratio can and does turn some non-interference engines into interference engines.

posted by  vwhobo

Okie Dokie, I understand interference engines now. Maybe I don't have the need for you to go into non-interference (little confused). BUT, if you want to elaborate on the later, I would be more than happy to read, Hell, someone else may too. I know how much you love to type :laughing:

posted by  lectroid

Thank you VWHOBO.....I could not find any comprehensive listings either but I am going to check this out right now. Again, thanks for your help and thanks for saving me the effort of explaining what Interference and N on-I are. :hi: :smoke:

posted by  cmeseadoin

Ok VWHOBO,

I went to that chart and it has a ton of info, but I am looking to see if a 1996 Pontiac Grand AM 2.4L 4-cylinder has an interference engine. This listing cannot be found on this PDF. Do you know if that motor is Interference? Thank you!

posted by  cmeseadoin

Well, if you would have just asked the question you wanted answered it would have saved us all a lot of time. Is dealing with the sudden influx of dipshits getting to you... Like maybe rubbing off. :mrgreen:

The simple answer to that simple question is affirmative.

posted by  vwhobo

Well I have a few engines I wanted to look at so that is why I wanted the listing. :smoke: The immediate need though was for the 96 G/A. So thank you for your answer, I figured it was. :doh: Thanks again! :thumbs:

posted by  cmeseadoin

Vw,

You ever done them on that DOHC engine, the 2.4L? I am sure you have, are they a M/f'r to do? Looks like it due to clearance. Was thinking of losing the passenger motor mount and passenger tire and inner fender liner that covers the crank pulley, etc. I want to do it preventativly and prolly throw a water pump at it while I am in there, what do you think? Thanks!

posted by  cmeseadoin

You would be correct in your assessment. Mechanically and technically it's a very straightforward job. Clearance IS the issue. Just take yor time and walk away when you get pissed off, and you will get pissed of.

It's a good call to replace the water pump while you're there and just in case you did, don't forget to replace the tensioner and guides a well. You can get the whole set for just a little more than the chain alone.

posted by  vwhobo

Oh god I KNOW I will get pissed off. I will have to try not to start throwing things, LOL.... :hi: I will end up saying :fu: to that car more times that I have hairs on my head because I have already looked at it and figured that with the motor mount gone, I will have to raise and lower the engine numerous times to get to all the bolts, etc. Mechanically it is easy. Oh, in your posting you said "chain?" I take it you meant belt? :hi: I just had to get on you for that one based on your "proper terminology" arguements. :laughing:
Thanks for the help and info. :thumbs:

posted by  cmeseadoin

Vwhobo,

Before you land blast me, let me correct myself. I "thought" that 2.4L had a timing belt but it DOES has a chain. I thought you just mis-spoke when you said "chain" in your previous posting to me because I have refered to the "belt" in all of my postings. Well hell, if it has a chain; I only have 50-55K on the engine; She isn't coming apart then unless I start having a water pump problem. Screw that, I thought I had a belt and was going to preventatively replace it here in the near future, esp. being an interference engine. Thanks for the help and again, my bad, I thought youoff when in fact, I did not realize I had a chain BUT the dealer confirmed it for me. Thanks :thumbs: :thumbs:

posted by  cmeseadoin

There is a list for timing belts at:

http://www.gates.com/brochure.cfm?brochure=981&location_id=540

But does naybody know of such a website for timing CHAINS? My 1988 Beretta (2.3 L V-6) just broke a timing chain and I was wondering if it might be worth me reparing. No way if it needs valves too! It died at freeway speeds! At least that is what I think is wrong as the starter now spins so fast as if no load at all. I assume there is no compression. Does GM still use those silly nylon sprockets?
-Don-

posted by  DonTom

That is not good. Your engine should have compression still and if the starter is spinning the engine over like there is no load, you have more than likely blown the pistons through with a valve/piston collision. I would have to check more into it, but when the timing chain/belt breaks, you do not lose compression. Granted the valve train does bring some level of resistance to the starter and adds to the compression, it is not enough to make the motor spin totally free once the chain/belt is no longer connected.

posted by  cmeseadoin

Remember the timing chain is broke, that equals stuck open valves which equals no compression....

posted by  DodgeRida67

Yes that is very true, that went right past me for some reason :doh: .....if it is an interference engine though, it may be severly damaged....if not, then there should have been clearance for the pistons and valve train when they were out of time with one another. Great call...I was not thinking! :ohcrap:

posted by  cmeseadoin

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