Is This Engine Still Good? (Compression Numbers)
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From: Texas
Is This Engine Still Good? (Compression Numbers)
1-135 (141 Wet). 2-135
3-134 (140 wet). 4-131
5-130 (130 wet). 6-126
7-145 (147 wet). 8-150
Sorry, I didn’t get the wet PSI for the other side. It was enough of a pain in the *** getting the hose in, and out the first time.
3-134 (140 wet). 4-131
5-130 (130 wet). 6-126
7-145 (147 wet). 8-150
Sorry, I didn’t get the wet PSI for the other side. It was enough of a pain in the *** getting the hose in, and out the first time.
Racer
Joined: Feb 2019
Posts: 397
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From: Jackson, mi
number 6 is a little low but not enough to really worry much about if its just a cruiser type car, its within the 20% range, if you are capable of doing you're own valve job on a bench. maybe that would be all it needs to bring those numbers closer together again and by doing you own i mean just hand lapping them with some compound and cleaning the valve seats up, its not that hard really i use a power drill and some 1/4 inch id fuel line on a 5/16 drill bit with hose clamps tightened up good,then put the other end on the valve stem, run it one direction then backwards several times util you hear it start to sound nice n smooth it works great and saves a lot of time. i love doing budget stuff like that it saves money for better things
Oil Producer
Joined: Apr 2014
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https://youtu.be/0cK8tt6FdCs
this is how i "ground" my valve seats. it worked awesome.
forgive my narrative, it was my very first engine and im sure there are things i said that are not true. but i can verify this works well. if done right.
this is how i "ground" my valve seats. it worked awesome.
forgive my narrative, it was my very first engine and im sure there are things i said that are not true. but i can verify this works well. if done right.
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Joined: Nov 2018
Posts: 71
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From: Texas
number 6 is a little low but not enough to really worry much about if its just a cruiser type car, its within the 20% range, if you are capable of doing you're own valve job on a bench. maybe that would be all it needs to bring those numbers closer together again and by doing you own i mean just hand lapping them with some compound and cleaning the valve seats up, its not that hard really i use a power drill and some 1/4 inch id fuel line on a 5/16 drill bit with hose clamps tightened up good,then put the other end on the valve stem, run it one direction then backwards several times util you hear it start to sound nice n smooth it works great and saves a lot of time. i love doing budget stuff like that it saves money for better things
Racer
Joined: Feb 2019
Posts: 397
Likes: 29
From: Jackson, mi
is it smoking or anything? running poorly? to be honest in my opinion, no its not much to worry about usually when you have a cracked ring you have around 50 psi or so. if you look at the video link viking posted there he shows the little carbon deposit in his valve seats, even that little bit will cause some minor compression loss. you might even get away with some .. cant think of the name right now.. but its the cure all for engines haha.. man its on the tip on my tongue but follow the directions and it says how to use it for cleaning valve train. its not lucas but that other stuff.... ooo sea foam, maybe try some sea foam and see what it does, ya never know for 8 bucks a can its worth a shot before you tear it apart. i would fill the tank up pour a can of sea foam in the tank and then buy another can and use it to pour into the intake as per instruction on cleaning valves.then in a month or so after the tank of gas is used, try another compression test and see if it helped at all
Last edited by bud40oz; Feb 5, 2019 at 09:49 PM.
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From: Texas
Whenever I drive about an hour on the freeway then exit, and hit my first stop light it stalls out, then when I turn the key it starts right back up. I think it may be the EGR valve staying open. Idle is a bit rough too. Swapped out the air filter, fuel pump, fuel filter, spark plugs, spark plug wires, ignition coil, cap, rotor, TPS, IAC, O2 Sensor, cleaned out throttle body and it’s still rough. I did a Fuel Pressure Test at start up, and under load conditions up to 70 mph. The fuel Pressure was perfect. It does have crappy acceleration when I try to accelerate gradually, but if I go full throttle it hauls ***.
Last edited by 89’Vette; Feb 6, 2019 at 10:09 AM.
Thread Starter
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Joined: Nov 2018
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From: Texas
is it smoking or anything? running poorly? to be honest in my opinion, no its not much to worry about usually when you have a cracked ring you have around 50 psi or so. if you look at the video link viking posted there he shows the little carbon deposit in his valve seats, even that little bit will cause some minor compression loss. you might even get away with some .. cant think of the name right now.. but its the cure all for engines haha.. man its on the tip on my tongue but follow the directions and it says how to use it for cleaning valve train. its not lucas but that other stuff.... ooo sea foam, maybe try some sea foam and see what it does, ya never know for 8 bucks a can its worth a shot before you tear it apart. i would fill the tank up pour a can of sea foam in the tank and then buy another can and use it to pour into the intake as per instruction on cleaning valves.then in a month or so after the tank of gas is used, try another compression test and see if it helped at all
Last edited by 89’Vette; Feb 6, 2019 at 10:11 AM.
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From: Texas
Thread Starter
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Joined: Nov 2018
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From: Texas
So I put the Sea Foam into the Intake. It didn’t smoke too much, but a decent burst came out. Still going to swap out the EGR Valve, EGR Solenoid, and Fuel Injectors.
Last edited by 89’Vette; Feb 7, 2019 at 10:45 AM.
Melting Slicks
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From: Park Ridge New Jersey