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Stef's 7A-FE Rebuild - 6G Celicas Forums

Topic #51960 186 posts Started by hurley97
the springs and retainers would probably work fine.



a little late of an UPDATE: So Christmas day, with under 500 miles on the new engine, Dustin and I decided to drive my car down to NJ and from the beginning something was wrong. the car would not heat up like it should, when it finally got some temperature the heat would blast cold air, the oil pressure dropped a little lower than it should have been. about 15 mins from home the check engine light came on and the car stalled out.

opened the hood and found out the lower radiator hose had come off and all my coolant drained out. I had a tiny amount of water and coolant leftover from the swap but we connected the hose back up and poured in what we had and decided to try and limp the car home.

we made it just about far enough to turn around and get a little past where we stopped the first time before the temp needle moved just over normal operating temp. that was it, shut the car off and called a tow truck. first time my car has ever had to be towed and it was with the new motor, I was very upset.

took Dustin's car to NJ and when we got back that night made sure the radiator hose was secure and filled it with coolant/water just so I could get it to work and have them do a proper coolant flush.

now that the coolant situation is all set I did notice an oil leak. having checked it out further at work I think it's a defective crank seal. my oil pan is wet with oil and the furthest part of the moisture seems to be coming from the bottom corner of the timing cover just behind the crank pulley. pulled the top part of the timing cover off and the cam seal and everything around it is dry. it has still not been taken care of but it's not leaking terribly, it's maybe lost 1/2 qt in 1200 miles.

on a positive note the rings are seating perfectly, the oil is constantly cleaner than I have ever seen it before. and I am very happy with my cams, they make the car pull like no other 7A can and they make me feel much better about the car.

This post has been edited by hurley97: Jan 13, 2008 - 11:50 AM

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
all motor builds come with their hickups. sounds like you got it handled though. whats the ET on turboing?

94' ST Coupe - 5sfe Motor swap and brake swap.
replaced the crank seal on Weds. it had popped out on one side.

I need to get my wideband hooked up again but now Innovate wants me to take it out and send it back to them for a failure analysis and they will either fix it or send me a replacement... and who knows how long that will take.

turbo setup will probably be waiting until late spring. I'd like to give the engine some break in time, if there are going to be any other hiccups I want to get them out of the way.

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
Nice write up on the 7AFE.

I am curious about the cam you put in as it has a lot more duration than a stock cam. Did you loose much low end? What rpm does it start pulling hard and how high does it pull now? My stocker (except for a header) is all done at about 6000.

I think it's about the same on the low end, it just feels like you loose a little because of the pull later on.

It starts to pull hard between 3500-4000 rpm and continues to pull all the way to redline, I haven't gone past redline yet but I'm pretty sure it'll pull past it.

Also, it dramatically changes the sound of the engine. There's the normal low rpm quit, changes sound completely and gets louder in the mid range, and it makes a hell of a noise after 5000 rpm.

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
you said you havent gone past redline, did you change the fuel cut on the ecm so that it can go past the preset 6200 or not? if so, how did you change it?

1994 GT Hatchback1994 ST Coupe1988 Corolla Wagon All-Trac1999 Corvette2008 Cobalt SS Turbo
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QUOTE(94celicadude @ Feb 20, 2008 - 4:53 PM) [snapback]643754[/snapback]
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you said you havent gone past redline, did you change the fuel cut on the ecm so that it can go past the preset 6200 or not? if so, how did you change it?

mine is a 97 so my redline is about 5900. I did not bypass the fuel cut, I believe it will set off a check engine light once you go past redline if you do bypass it. If you want to know how to do it go here: http://evilspeed.com/Speed_defeat.htm

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
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QUOTE(hurley97 @ Feb 21, 2008 - 3:18 AM) [snapback]643881[/snapback]
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QUOTE(94celicadude @ Feb 20, 2008 - 4:53 PM) [snapback]643754[/snapback]
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you said you havent gone past redline, did you change the fuel cut on the ecm so that it can go past the preset 6200 or not? if so, how did you change it?

mine is a 97 so my redline is about 5900. I did not bypass the fuel cut, I believe it will set off a check engine light once you go past redline if you do bypass it. If you want to know how to do it go here: http://evilspeed.com/Speed_defeat.htm



i believe he means did you remove/raise the RPM limiter, not speed limiter.

What do you think our bottom end can take? i know a stock valve train does not like >6,000RPM, though

QUOTE"And, as always, your friendship, help, and dedication to the advancement of Texas Celica dominance is GREATLY appreciated. Thanks bro." -DEATH1994 GT:V6 swap, 5speed E53 W/ LSD, All Power, now RED1995 ST:SOLD @273k miles, Auto, all power, CarPC, White1994 ST:Totaled, 5spd, all power, RedRIP 07/09/09 @ 241,8101994 Lexus LS400:This is my new DD
he said "fuel cut" which is pretty much what limits the speed. and as far as I know thats the only limiter you can modify.

I think the bottom end can take more than you would think. Manny (presure2) ran his 5S up to about 8200 rpm or so (accidentally) once, still runs great.

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
honda guys only have to replace a crystal in the ECU.
im not sure about us..
8200 RPM would not be too safe daily.. lol
did it pull strong up that high?

QUOTE"And, as always, your friendship, help, and dedication to the advancement of Texas Celica dominance is GREATLY appreciated. Thanks bro." -DEATH1994 GT:V6 swap, 5speed E53 W/ LSD, All Power, now RED1995 ST:SOLD @273k miles, Auto, all power, CarPC, White1994 ST:Totaled, 5spd, all power, RedRIP 07/09/09 @ 241,8101994 Lexus LS400:This is my new DD
Have you dyno'd this new engine?

--------------------------------私は銀行に漂う,TRDInspired
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QUOTE(hurley97 @ Feb 20, 2008 - 10:53 PM) [snapback]643894[/snapback]
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he said "fuel cut" which is pretty much what limits the speed. and as far as I know thats the only limiter you can modify.

I think the bottom end can take more than you would think. Manny (presure2) ran his 5S up to about 8200 rpm or so (accidentally) once, still runs great.



If your still rocking the shims over buckets, then you cant rev it very high. Maybe 7k tops. If you go any higher then that, you risk the shims flying out and causing a huge mess.
You should be able to use the emanage to raise your stock rev limiter if you want to.

15PSI - 30MPG - Megasquirt Tuned
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QUOTE(Daftboy @ Feb 20, 2008 - 11:43 PM) [snapback]643919[/snapback]
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Have you dyno'd this new engine?

no. I think that would end up being very disappointing. It feels much smoother and it's definitely faster. As it is now the car is 100% better than it was when I got it four years ago. I've put a lot into this car and I'm happy with it right now, I'm not too concerned with the numbers just yet.

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
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QUOTE(hurley97 @ Feb 22, 2008 - 9:22 PM) [snapback]644763[/snapback]
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QUOTE(Daftboy @ Feb 20, 2008 - 11:43 PM) [snapback]643919[/snapback]
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Have you dyno'd this new engine?

no. I think that would end up being very disappointing. It feels much smoother and it's definitely faster. As it is now the car is 100% better than it was when I got it four years ago. I've put a lot into this car and I'm happy with it right now, I'm not too concerned with the numbers just yet.

Yeah but I am! laugh.gif wink.gif
so I have some problems...

First, I'm pretty sure there is another oil leak. It's not bad but its there. The rear mount bracket, crossmember, and bottom of the transmission bell housing are wet with oil. The passenger side axle cup is a little moist too. That would indicate a bad rear main seal. Popping the little cover off and looking up into the space between the engine and bell housing you cannot see the seal sticking out at all, meaning the rear main seal did not pop out of place like the crank seal did. So either the seal itself is defective or... what else could leak behind there?

Second, and slightly more importantly, I'm leaking coolant slowly into cylinder number 4.

I've heard a gurgling noise from the heater core ever since we installed the engine. I tried a few things thinking they would cure it and nothing has:
- Switched the coolant in and out hoses to the heater core thinking if they were backwards it would cause the noise, nothing.
- Flushed the coolant several times using different methods of getting out air pockets, nothing.
- Finally changed the radiator as a last resort thinking thats the only thing left that's different since putting in the new engine, now it doesn't do it all the time but I do still hear it a little. Maybe it needs more time?
- Pulled out all four spark plugs and the ceramic centers are all white except the one that came out of cylinder 4 which is a little pinkish. Not a good sign.
- Using a scope to look into the cylinders I could see two small drips of pinkish fluid come from right about where the cylinder head meets the block at the headgasket.
- When shining a flashlight down into the cylinders you can tell the top of piston 4 is a little more wet than the others.

The theories:
- The head is cracked or warped from the slight overheating. Theory being that if there was no coolant for the temp gauge to read so it was inaccurate and it actually overheated more than we thought.
- One or two of the headbolts that we reused were actually not reusable and did not stretch like they should have causing the headgasket seal to not be consistent.
- The sanding and leveling of the bottom surface of the head by the use of a straight edge and a mechanic's eye was not quite accurate enough and the mating surface is uneven.
- The headgasket itself is defective.

Proposed cure:
Send out the spare head from my old engine for inspection, cleaning, machining, shaving, valve angling, everything. Swap over my shims, buckets, and cams. Replace the headgasket, valve seals, headbolts, and any other associated gaskets that need to be removed. In theory that should take care of all the theoretical causes of the problems addressed in all my theories above. I need to know if I sound crazy or if that sounds like a good theoretical plan...

Current mood: frown.gif

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
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>First, I'm pretty sure there is another oil leak. It's not bad but its there. The rear mount bracket, crossmember, and bottom of the transmission bell housing are wet with oil. The passenger side axle cup is a little moist too. That would indicate a bad rear main seal. Popping the little cover off and looking up into the space between the engine and bell housing you cannot see the seal sticking out at all, meaning the rear main seal did not pop out of place like the crank seal did. So either the seal itself is defective or... what else could leak behind there?


take a look at your distributor o-ring and inside the distributor cap. I had a similar leak and had to fully rebuild the distributor and install it with 2 orings before it would stop. Since the distributor is right above the crank/trans, it could be all just dripping down.

As for the motor itself, I wouldn't tear into it without doing a leak down test.

Where did you get a borascope from and how much was it? I want one!

This post has been edited by lagos: Apr 21, 2008 - 9:31 PM

15PSI - 30MPG - Megasquirt Tuned
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QUOTE(lagos @ Apr 21, 2008 - 10:29 PM) [snapback]666845[/snapback]
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>First, I'm pretty sure there is another oil leak. It's not bad but its there. The rear mount bracket, crossmember, and bottom of the transmission bell housing are wet with oil. The passenger side axle cup is a little moist too. That would indicate a bad rear main seal. Popping the little cover off and looking up into the space between the engine and bell housing you cannot see the seal sticking out at all, meaning the rear main seal did not pop out of place like the crank seal did. So either the seal itself is defective or... what else could leak behind there?


take a look at your distributor o-ring and inside the distributor cap. I had a similar leak and had to fully rebuild the distributor and install it with 2 orings before it would stop. Since the distributor is right above the crank/trans, it could be all just dripping down.

As for the motor itself, I wouldn't tear into it without doing a leak down test.

Where did you get a borascope from and how much was it? I want one!

If the leak was coming from the distributor it would be on top of the transmission, yes? The top is dry.

It's such a small coolant leak it probably wouldn't even show up in a leak down test. I already asked.

The borascope belongs to work, I just use it. I have absolutely no idea how much it costs.

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
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If the leak was coming from the distributor it would be on top of the transmission, yes? The top is dry.


No. It just drips down the side of the block as it slowly leaks down. Feel around your distributor harness plug to see if its wet, or the area on the block right under it. If your on the original distributor, there is a good chance that the old rubber seal inside of it is shot.

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>It's such a small coolant leak it probably wouldn't even show up in a leak down test. I already asked.


Then honestly, I wouldnt tear anything apart to try to fix it. You may go through all time time/cost just to find out it was caused by something totally unrelated. As long as the car is not overheating, I wouldn't worry about it, and just see what happens.

15PSI - 30MPG - Megasquirt Tuned
I'm pretty sure I looked all round the top of the motor and didn't see anything but it's worth another look with attention to that specific area. Thanks for the advice.

Thats the crazy part, the car runs perfectly. Never overheats, no smoke out the back at all, nothing but the little moisture ans pink color on the one plug and the slight noise which I haven't heard the last two times I started the car cold.

BUT, I know theres a problem and it bothers me. If I'm going to put the added stress on the motor I want it to be virtually flawless since any problem I do have right now is only going to get exponentially worse a few months from now.


Right now everything is washed down and levels are noted and I'm going to keep a close watch on what happens next to narrow things down a little more.

This post has been edited by hurley97: Apr 21, 2008 - 10:02 PM

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
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>BUT, I know theres a problem and it bothers me. If I'm going to put the added stress on the motor I want it to be virtually flawless since any problem I do have right now is only going to get exponentially worse a few months from now.


Think of it this way... If you really do have a small coolant leak from the head gasket, and it does get worse when you boost the motor, whats the worst thats going happen? Your situation wont be any worse.
On the other hand, you might do all this work, and still hear the noise from your heater core.

15PSI - 30MPG - Megasquirt Tuned
jeee i really don't want to post this; i'm probably gonna get flamed. kindasad.gif

But when there is a small leak, the over-the-counter stop a leak stuff at autozone or kragen works.

to be honest, if you want perfect; send the engine out to a machine shop and have both the head and block decked. But what its worth, you will most likely have to pull the entire engine apart to fix it. So its worth a shot to give the $15 stop a leak a chance.

I suggest to fix the problem as fast as you can. I've had an engine rebuild failure where the problem got worse and worse to the point where water was getting into the oil givine me 10-30 capuchino.

*puts on flame suit*

good luck

This post has been edited by Hanyo: Apr 22, 2008 - 5:45 AM
I'm looking for a permanent solution to the problem not a temporary band-aid.

I didn't think that the top surface of the block might have to be machined as well, that could be a problem. I was hoping it would be as quick and easy as just swapping the heads.

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
I would start by re torquing the head bolts. Also if you start shaving head and or block
you should keep track of what is removed as this will up your CR, the difference can be made up
with a thicker head gasket.

This post has been edited by 97lestyousay: Apr 22, 2008 - 2:26 PM

JDM guy made me do it.
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>Think of it this way... If you really do have a small coolant leak from the head gasket, and it does get worse when you boost the motor, whats the worst thats going happen? Your situation wont be any worse.
On the other hand, you might do all this work, and still hear the noise from your heater core.


Stef you definitly need to fix the problem before boosting mad.gif . Any foreign things in the combustion chamber i.e. coolant, oil, etc. can and will cause detonation. frown.gif Boosting the 7afe is very delicate and almost has to have perfect chamber conditions in order to last. The added pressure to the head from boosting (if it is the head gasket) will almost be guaranteed to get worse or fail. Trust me I know. wink.gif

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> But when there is a small leak, the over-the-counter stop a leak stuff at autozone or kragen works.


Im not burning you Hanyo and i agree this stuff does typically work, but it is a bandaid and it does eventually cause other cooling problems. Not a goos solution for a motor with so much investment.

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>I didn't think that the top surface of the block might have to be machined as well, that could be a problem. I was hoping it would be as quick and easy as just swapping the heads.


The block even if it has overheated more than likely will not have to be machined, these blocks are very resitive to warping and i have built several turbo 7afe from junk yard motors and they have never needed machining. The head on the other hand almost always does if it has over heated any bit. But be careful you will need to keep your c/r as low as possible for that turbo.

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>The theories:
- The head is cracked or warped from the slight overheating. Theory being that if there was no coolant for the temp gauge to read so it was inaccurate and it actually overheated more than we thought.
- One or two of the headbolts that we reused were actually not reusable and did not stretch like they should have causing the headgasket seal to not be consistent.


The celica thermostadt from my experience is VERY inaccurate. I have ran an extra thermo for a little over a year now and found a BIG diffenrence in the read out of factory and the aftermarket. I would suggest and oil press and aftermarket thermo before turboing just to have that extra security. wink.gif

smile.gif Its is not worth the chance of having to do another head job or engine failure to reuse old head bolts. smile.gif
I called the engine/machine shop we use at work (when they used to rebuild heads instead of order new ones) and they gave me a price of about $450. That includes inspection, cleaning, cutting the valves, valve seals, machining everything straight.

I'm really not sure if thats a good price, I don't know how much these things go for.

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
Real quick 'cause I don't have a lot of time;

The oil's not from your dist, you have an A series engine. It's a straight 4, not a slant 4, and IIRC the dist runs off the exhaust cam, putting the dist way up front, and straight above the trans, not hanging over like on the 5S.

Are you sure it's engine oil and not gear oil?
It's possible the input shaft seal is leaking, did you replace it when you put the trans in?

There's also another gasket for the rear main housing, as well as a worn crank [rubber seals wear the crank down over time].
What about the oil pan? They're a PITA to seal perfectly, especially on the ends where the main seal housings are.


How clean is #4 compared to the rest?
Have you tried a coolant tester? See if that forces any in.

$450 doesn't seem too bad if they're assembling the entire valve train for you in addition to all that work.
To save $ you can have them just machine the head surface and recut the valve seats. How did the valve guides look?
One word of warning, if you machine the valve seats you WILL need to reshim, and possibly cut the valve tips.
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QUOTE(alltracman78 @ Apr 24, 2008 - 8:12 PM) [snapback]667863[/snapback]
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Real quick 'cause I don't have a lot of time;

The oil's not from your dist, you have an A series engine. It's a straight 4, not a slant 4, and IIRC the dist runs off the exhaust cam, putting the dist way up front, and straight above the trans, not hanging over like on the 5S.

Are you sure it's engine oil and not gear oil?
It's possible the input shaft seal is leaking, did you replace it when you put the trans in?

There's also another gasket for the rear main housing, as well as a worn crank [rubber seals wear the crank down over time].
What about the oil pan? They're a PITA to seal perfectly, especially on the ends where the main seal housings are.


How clean is #4 compared to the rest?
Have you tried a coolant tester? See if that forces any in.

$450 doesn't seem too bad if they're assembling the entire valve train for you in addition to all that work.
To save $ you can have them just machine the head surface and recut the valve seats. How did the valve guides look?
One word of warning, if you machine the valve seats you WILL need to reshim, and possibly cut the valve tips.


Right, it's definitely not the distributor.

Yes, it is engine oil... or at least it doesn't smell like gear oil. The axle seals are new and neither of them are what's leaking, thats the first place I looked since that would be easier to change.

Yes, it could also be the housing gasket, that was the other theory. Either way the transmission has to come off so I guess I'll find out then. I'm pretty sure it's not the oil pan itself but again, it's worth another look with attention to that.

All the spark plugs looked very good actually, the only difference was the white ceramic in the middle. 1, 2, and 3 spark plugs were white and center of number 4 is pinkish

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06
Input shaft seal, not axle seals. smile.gif
They won't leak all over the bottom of the trans.
It's coming from some where in the center, and the airflow is blowing it across the bottom of the engine.
Whatever it is, like you said, you have to pull the trans off regardless, so you should be able to find it.

Have you checked your price for a brand new head?
It's probably recockulous, but it won't hurt to check.
No matter how good the machinist and tools, you can't beat a brand new head for trueness, or for good valve seats.

Coolant stop leak is crap. It can clog up your radiator, heater core, screw up the water pump, ect.
If you need it for an absolute emergency, it will do. Your case doesn't qualify [I know you weren't going to use it, just for general FYI].
But as soon as possible it needs to be flushed out.

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QUOTE(boostcrazy @ Apr 22, 2008 - 2:39 PM) [snapback]667111[/snapback]
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Any foreign things in the combustion chamber i.e. >>coolant>>, oil, etc. can and will cause detonation.


I hate to be an ass, but coolant can not, and will not cause detonation.
It will actually prevent it, just like water injection.
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QUOTE(alltracman78 @ Apr 24, 2008 - 8:34 PM) [snapback]667870[/snapback]
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Input shaft seal, not axle seals. smile.gif

Have you checked your price for a brand new head?
It's probably recockulous, but it won't hurt to check.
No matter how good the machinist and tools, you can't beat a brand new head for trueness, or for good valve seats.

laugh.gif that one took me a while

actually I just did after you suggested it, much less than I expected. Toyota World says $585. I think that's just the head only though, no valves.

7A-FTE:It's not about the money.Our Beams Swap.I <3 Dustin---07/16/06