B20b4 HELP PLEASE!!
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B20b4 HELP PLEASE!!
So i bought a 1998 crv on friday with 130000 miles on it and assumed the timing belt had been done but i assumed wrong... timing belt went out on me saturday when i was three hours away from home.. Was driving on ifive at about 70 and notice my car felt a little slow not like it is fast or anything but felt really strange.. like a min later it bogged down so i took my foot off the gas and pressed it again and still bogged so i pulled over to the side of the freeway and and tryed starting it wouldnt start try like 3 or 4 more times nothing... could tell the top end wasnt spinning. Got home and pull the vavle cover off and notice the timing belt wasnt broke but very very lose could pull it off the cam gears with one finger... SO MY QUESTION is do you guys think that my head is toasted like some bent vavles or what i didnt hear no werid nosies when all this happen or nothing? SO WHAT DO YOU THINK MY CHANCES ARE THAT MY HEAD IS STILL GOOD? Help please. let me know what you think.
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Re: B20b4 HELP PLEASE!!
Well i figured that much. I am going to put a timing belt on and see if it runs good..check compresion go from there... Do you think i could have ****ed up the bottom end at all? Every case i hear about like this people just bend valves.
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Re: B20b4 HELP PLEASE!!
A warning about just putting a timing belt on. You can bend a valve, but it'll still seal fine due to the valve spring "pressure" pulling the valve closed. After a period of use in this condition the valve neck will weaken due to constant flexing as it's closed, and will eventually break and drop into the cylinder. I would highly recommend two tests:
1st, Put the cams & crank in time, do put the timing belt on, don't start the engine, check all your valve clearances. If you have any that are excessively loose (out of spec) then more than likely (99% chance) it's bent.
2nd, Even if the valve clearances are in spec, take the head off, check each piston for marks where valves hit, check valves for signs of contact with the piston. If you see any indication or possible indication of contact, disassemble the valve train (remove the valve springs) and check each suspect valve for a slight bend. It's easiest to tell by either spinning the valve by it's stem between your hands, rolling on a smooth table (don't drop), or standing them all side by side on a table (in order & position of removal) and comparing. Another way is doing a leak test by holding the valve closed by hand with the spring removed & spraying brake wash into the intake port behind the valve & check for fluid leaking past the valve into the combustion chamber.
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Re: B20b4 HELP PLEASE!!
When the pistons hit the valves, the valves will mark the pistons. Often it's just knocking the carbon off the face of the piston, maybe some scuffing as the valve shifts as it's bent. Yes it's rare, but it's possible for a piston to crack from this, but again rare.
A warning about just putting a timing belt on. You can bend a valve, but it'll still seal fine due to the valve spring "pressure" pulling the valve closed. After a period of use in this condition the valve neck will weaken due to constant flexing as it's closed, and will eventually break and drop into the cylinder. I would highly recommend two tests:
1st, Put the cams & crank in time, do put the timing belt on, don't start the engine, check all your valve clearances. If you have any that are excessively loose (out of spec) then more than likely (99% chance) it's bent.
2nd, Even if the valve clearances are in spec, take the head off, check each piston for marks where valves hit, check valves for signs of contact with the piston. If you see any indication or possible indication of contact, disassemble the valve train (remove the valve springs) and check each suspect valve for a slight bend. It's easiest to tell by either spinning the valve by it's stem between your hands, rolling on a smooth table (don't drop), or standing them all side by side on a table (in order & position of removal) and comparing. Another way is doing a leak test by holding the valve closed by hand with the spring removed & spraying brake wash into the intake port behind the valve & check for fluid leaking past the valve into the combustion chamber.
A warning about just putting a timing belt on. You can bend a valve, but it'll still seal fine due to the valve spring "pressure" pulling the valve closed. After a period of use in this condition the valve neck will weaken due to constant flexing as it's closed, and will eventually break and drop into the cylinder. I would highly recommend two tests:
1st, Put the cams & crank in time, do put the timing belt on, don't start the engine, check all your valve clearances. If you have any that are excessively loose (out of spec) then more than likely (99% chance) it's bent.
2nd, Even if the valve clearances are in spec, take the head off, check each piston for marks where valves hit, check valves for signs of contact with the piston. If you see any indication or possible indication of contact, disassemble the valve train (remove the valve springs) and check each suspect valve for a slight bend. It's easiest to tell by either spinning the valve by it's stem between your hands, rolling on a smooth table (don't drop), or standing them all side by side on a table (in order & position of removal) and comparing. Another way is doing a leak test by holding the valve closed by hand with the spring removed & spraying brake wash into the intake port behind the valve & check for fluid leaking past the valve into the combustion chamber.
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Re: B20b4 HELP PLEASE!!
So i put a new timing belt and water pump kit on...started right up sounds nice compression seemed good. Getting a compression tester tomorrow to check them what psi should i have per cylinder in this thing?
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Re: B20b4 HELP PLEASE!!
However I see you already skipped that and put the new belt on, so oh well.
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Re: B20b4 HELP PLEASE!!
If you can see marks on the pistons by looking down through the spark plug holes with a flexible pen light, then yes I sure would. If there isn't a mark on a single piston then I'd probably let it go.
However I see you already skipped that and put the new belt on, so oh well.
However I see you already skipped that and put the new belt on, so oh well.
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