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1998 Mazda B2500 Question: My timing belt broke while going 55mph. Changed belt, now no compression

 

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Belt broke, 2.5L 4 Cylinder, San Pablo, CA, December 18, 2013, 14:26
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My timing belt broke while on the freeway, I was going about 55mph. From what I could find out it is NOT an interference motor, so I figured the valves should be okay, but for some reason cylinder 1 and 4 won't close all the way now, but they move up and down freely, I sprayed a little solvent in them hoping there just a little dirty, other than that I have no clue wats wrong, because I thought there shouldn't be a problem with the valves? Any help is greatly appreciated

Thanks, mike

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  • Answer #1

    pushrod December 18, 2013, 14:53
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    ANY overhead valve engine has the potential for valve/piston interference under the right conditions!! Compression ok on 2&3??
    Same vehicle, imagine that. You get around, huh.

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    Belt broke, December 18, 2013, 16:12
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    Yea compressions fine on 2 and 3. And I think your talking about the earlier post, his post is actually what lead me here, I googled 98 Mazda b2500 timing belt broke and now no compression cylinders 1 and 4, and that was the first thing on the list. I've already changed the belt and tensioner and water pump and now no compression, do you think the valves could be bent?

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    pushrod, December 18, 2013, 16:14
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    Must be since 2&3 are ok!

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    Belt broke, December 18, 2013, 16:22
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    Ok thanks a lot for your help

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  • Answer #2

    G. T. Service Center (4071 Answers) , Stephenville, TX - (254) 638-3236
    ProfessorG December 18, 2013, 15:40
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    I've had overhead valve engines bend valves under the right conditions. Timing belt broke while driving, now no compression. Pull the head, you have bent valves., End of story, Sorry.

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    pushrod, December 18, 2013, 15:54
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    If it is back in correct time now, i agree! Reason i ask about the other cylinders,, if they have compression then you be right on! But if all are low well....yeah, i know said was not closing but dont hurt to check it out.

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    ProfessorG, December 18, 2013, 16:07
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    I just get like you, I already was told off for advice, when all the information wasn't given. Just throwing another thought to a wanna-be.

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    pushrod, December 18, 2013, 16:15
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    Got ya!

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    Belt broke, December 18, 2013, 16:20
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    I didn't see this post before I sent my other reply, so the valves are definatly bent huh? Damn, ok so if I take off the head wat else should I change while I'm in there?

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    ProfessorG, December 18, 2013, 16:38
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    You'll need a head gasket set, A valve spring tool, valve compound, and the valves needing to be replaced. Always check the head for warpage while it's off. Shouldn't need anything else unless a visual inspection shows something that needs attention.

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