Bent valve replacement
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Bent valve replacement
Timing gear went out a few months back. No spark, no compression, camshaft does not spin. Gears are bad. Engine has bent valves.
As a preface this engine has 201,000 miles. I bought it at 105,000, soon after an engine rebuild. I pulled a 2800 lb travel trailer on a couple big trips the past couple summers and it finally gave out.
I am really fond of this truck, as it has been well maintained.
So, rebuild or new remanufactured is the options. Any suggestions. I am not the mechanic. What are the likely costs involved.
As a preface this engine has 201,000 miles. I bought it at 105,000, soon after an engine rebuild. I pulled a 2800 lb travel trailer on a couple big trips the past couple summers and it finally gave out.
I am really fond of this truck, as it has been well maintained.
So, rebuild or new remanufactured is the options. Any suggestions. I am not the mechanic. What are the likely costs involved.
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1988 300 4.9 efi manual air in heads
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If you are not a mechanic, start looking for a reman'd engine.
Bent valves may have nicked up the piston or cylinder wall. You won't really know that until you pull the head.
The price for a reman will tell you about what the repairs will be. Your engine has 100k+ on it, so any reman you do or have done will involve lots of new parts anyway.
All of that is unknown until there is a tear down.
Bent valves may have nicked up the piston or cylinder wall. You won't really know that until you pull the head.
The price for a reman will tell you about what the repairs will be. Your engine has 100k+ on it, so any reman you do or have done will involve lots of new parts anyway.
All of that is unknown until there is a tear down.
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From: Boise, Idaho
What makes you think it has bent valves?
The 300/4.9 is a non-interference engine, so if the timing gears go, it just spins around and dies.
Pull the oil pan off, clean out the shredded timing gear bits and pieces so they don't clog the oil pump, put on new timing gears, and fire it back up.
If you know it has bent valves, it's still a non-interference engine. Bent valves won't touch the pistons/piston walls. You can pull the head and just have the head rebuilt with new valves.
The 300/4.9 is a non-interference engine, so if the timing gears go, it just spins around and dies.
Pull the oil pan off, clean out the shredded timing gear bits and pieces so they don't clog the oil pump, put on new timing gears, and fire it back up.
If you know it has bent valves, it's still a non-interference engine. Bent valves won't touch the pistons/piston walls. You can pull the head and just have the head rebuilt with new valves.
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From: Angier, NC
or is that for the reman and then what is the 300 for?
Then you have 1400 for R&R I am guessing?
So who said the valves are bent?
I did not think the 300 motor or any of the OHV Ford motors bent valves if the gears (on a six) chain went bad?
The motor will turn over faster than normal because the valve timing is not right.
The shop that might have said bent valves spends to much time on the newer OHC motors and yes they will bend valves if a belt lets go.
I also find it hard that the 300 six gears, no chain, went bad in under 100K but guess it could happen?
Dave ----
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Noninterference engine reply
What makes you think it has bent valves?
The 300/4.9 is a non-interference engine, so if the timing gears go, it just spins around and dies.
Pull the oil pan off, clean out the shredded timing gear bits and pieces so they don't clog the oil pump, put on new timing gears, and fire it back up.
If you know it has bent valves, it's still a non-interference engine. Bent valves won't touch the pistons/piston walls. You can pull the head and just have the head rebuilt with new valves.
The 300/4.9 is a non-interference engine, so if the timing gears go, it just spins around and dies.
Pull the oil pan off, clean out the shredded timing gear bits and pieces so they don't clog the oil pump, put on new timing gears, and fire it back up.
If you know it has bent valves, it's still a non-interference engine. Bent valves won't touch the pistons/piston walls. You can pull the head and just have the head rebuilt with new valves.
Because of the way it went out caused me to wonder. Just heard a rather minor snap and no other sounds. It reminded me of the non sound when my VW Betts timing belt went out.
The mechanic I brought to wrote that it had no spark and no compression, bad timing gear and possibly bent valves.
I will surely follow up.
Thanks
Bpcahill
I see now that AB posted his just before my post and I was like What??
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