Rebuild f23a4? Junk Yark Swap? Cliff Diver?

Blenton

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So I did a compression test today. Numbers are as follows.

#1 #2 #3 #4
Beginning: 150psi 60psi 60 psi 140psi
After valve adjustment: 150 psi 60 psi 60 psi 140 psi
Adding oil to cylinder: 70 psi 70 psi

To me, cylinders 1 and 4 seem low to begin with. Shouldn't they be around 190ish? I think that is what I've seen on other posts like for HondaLuvr's F engine. Obviously 2 and 3 are muckered up. No wonder it shakes like a jackhammer at idle.

Since 2 and 3 are adjacent cylinders, am i correct in thinking the head gasket may be leaking? Or is that just if the compression is 0 in two adjacent cylinders and I now have two cylinders with bad vavles? Also, a change in 10 psi when adding oil straight to the cylinder wouldn't indicate bad rings, would it? Or would the low initial compression (150 psi) in cylinder 1 indicate that there is a lot of wear on the rings and whatnot anyways?

I'm debating whether or not I yank the head and take a peak or just purchase a used motor. I found one with 81k miles on it that was in a rollover. But they have to ship it to me. If I go that route, I figure I'll pull the transmission and refresh it with new clutches, steels, and gaskets while I wait for the engine to arrive. With my luck, if I went through all the trouble of replacing the motor without rebuilding the transmission, it would go out in 1000 miles. Your thoughts, please....
 

NASOHC

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hmmm... sounds like it's time for a new motor.

I would get yours rebuilt. You never know what you may get from a wrecking yard, i don't care how clean it looks. If you can cough up the funds and don't want a whole new car, re-do the motor.

Piston kit and rngs, machine work and head job shouldn't cost more than $1000 if you deal with machine shop directly. If you can save more cash by pulling the motor yourself or friend even better. Put a new timing belt, tensioners, and water pump. After plugs, oil and misc. you should be around $1500+labor. You'll have acar running like new considering all other parts are working well. Great opportunity to clean out everything and make some cosmetic touches to engine compartment.

I love my new motor! :rock: Over 180k on chassis.
 

Blenton

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I got the motor torn most of the way down so the head and intake manifolds are off and out of the car. I was kinda hoping that the head gasket was the culprit so I could save some coin. But, alas, new motor it is... Here are some pics for you to view, just in case I missed something.

NASOHC - $1500 + labor is a little more than I'm willing to spend on this thing right now. I mean, that's almost half the car's value. And to be honest, there are some things I don't much like about the vehicle, the seats prolly being #1. But that's because I've been pampered by 7+ way power adjustable seats ever since I swapped some nice leather seats my bronco way back in high school. My exploder is a Limited, so it's got the same power leather seating. But I'm still debating it.

Just thinking out loud, but maybe I'll call the machine shop in the morning and get some more estimates. But I can't find a complete engine kit for less than $600, and I know the head will be about $350 to rebuild. I figure boring the block will be maybe $250, and $150 to turn the crank. Now add on $400 in miscellaneous (water pump, timing belt, plugs, wires, oil, coolant, etc). That's already $1750.

And, as mentioned earlier, if I pull the whole motor, I'm going to do the transmission while I wait. I've done several before from different makes (chevy, ford, kia, mazda, mercedes benz), so I'm hoping I can work my way through it. But the transmission kit is $150 and another $150 to have to the torque converter rebuilt. Plus $70 for fluid. So.... $2000+ for a car with 160k miles on it, but a new motor and trans... Or $2000 towards something else, like my tuition or a beater that's not as beaterish as this one. Blah. Decisions, decisions...

cylinders4.JPG


cylinders5.JPG


cylinders6.JPG


cylinders1.JPG


cylinders2.JPG


cylinders3.JPG


head_gasket1.JPG


head_gasket2.JPG


valves1.JPG


valves2.JPG


valves3.JPG


top_intake.JPG


bottom_intake.JPG


exhaust_manifold.JPG
 

HondaLuver83

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It looks like the previous owner never kept up on maintenance, oil changes ect. Im not sure, but I think I can see some ring wear on cylinder 2 and 3. The valves look okay, just dirty, you can re-grind valves and seats, head cleaned. It would probably take care of that.

Im not sure about the bottom end. Im not going to make any assumptions unless I can measure some tolerances.

BTW, these engines are real tough.....and I mean that. Whoever owned it before, probably hardly ever changed their oil. These engines are known to hold 300whp on a stock bottom end, which is really good considering thats twice what the engine is rated.



Hope this helps....
 
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Blenton

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UPDATE:
I've been out of town on business for 2 weeks and wasn't able to pick up the motor from my friend's warehouse until last night. I got the motor home, pulled off the plastic shrinkwrap, and took a gander at the timing cover. It said the motor was an F23a1... :( My car came with an F23a4... So I was just about to call the salvage yard and raise hell, but decided to do a little searching on the forum first. My results were a big hazy...

As I understand it, the head, block, and sensors are exactly the same between the f23a1 an the f23a4 EXCEPT for the exhaust manifold and O2 sensor (and ECU). Most of the posts were about swapping and f23a4 in place of an f23a1 and not the other way around. Since I am attempting to put an f23a1 in place of an f23a4, is it going to work if I simply put the exhaust manifold (with the accompanying o2 sensor) on the f23a1 block that the salvage yard sent me? Also, the one they sent didn't come with a distributor. Will my dizzy work with it?

I read several posts concerning the topic, and they mostly said that my above-mentioned idea is valid. But there was always one person that chimed in saying, 'I know some dude that swapped in an f23aX in place of his f23aY and it didn't work'. My Fed-Up-O-Meter is already maxed out with this car and I don't want to spend the time dropping in a different motor to find out it isn't compatible. So please, indulge me and tell me one more time whether or not the f23a1 will work in place of the f23a4...
 
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hotaccord243

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You should be able to do that. Just use your IM and O2 sensor from your f23a4 onto the f23a1 newer block and your good.

I know i did the same thing, used many parts from both the a1 and the a4, and it was done, however i have the standalone EMS so that could be a bit different.

If i'm thinking right though, yes it should work the way you stated. The distributor is interchangeable without any problems.
 

HondaLuver83

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You will have to get a F23A1 ECU as well, the O2 sensors for the Ulev are wideband, the ones for the F23A1 are not.
 

hotaccord243

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Yeah you would need the ECU, if you use the O2 sensor from the A1.

If you have the A4 in there now, with the A4 ECU, and you re-use the A4 ECU, O2 sensor and manifold, and plug those three in the same way you did before, with the A1 motor....

why spend the extra money on an a1 ecu? wouldn't that be a waste completely?

all it is a little different wiring for O2 sensor/manifold in combination with ECU. So if you keep the a4 ecu along with the corresponding parts, you shouldn't have to buy an ecu. am i not correct?
 

HondaLuver83

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Yeah you would need the ECU, if you use the O2 sensor from the A1.

If you have the A4 in there now, with the A4 ECU, and you re-use the A4 ECU, O2 sensor and manifold, and plug those three in the same way you did before, with the A1 motor....

why spend the extra money on an a1 ecu? wouldn't that be a waste completely?

all it is a little different wiring for O2 sensor/manifold in combination with ECU. So if you keep the a4 ecu along with the corresponding parts, you shouldn't have to buy an ecu. am i not correct?

Im pretty sure that would work. The A4 is rated at 147hp, the A1 is 150. Im sure the difference is the wide band O2 sensor and ECU Vs the A1 ECU and tune, so if you dont care about the 3 HP. Then just hook everything up normal. IMO, 3HP isnt worth a new ECU and other crap.


Also, dont worry. These arent FORDS, CHEVYS OR DSM cars. They will last a long time without issues, your personal problems with your accord are very isolated to say the least.
 
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hotaccord243

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The one advantage of the f23a1 vs. the f23a4 is the cylinder sleeve wall make up. It is much easier to bore out and replace then the a4. Some shops won't re-sleeve the a4 because of this difficulty in removing the old sleeves. I can't remember exact reason however, i know that i had to make sure mine was an f23a1 otherwise ERLperformance wouldn't sleeve it. (I guess this is only if you plan on building it though.... lol

Just thought i would throw that out there. I wish i could tell you which parts are from which F23a1/a4 but i went through a couple and can't remember what i re-used haha.
 
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