About to give up... truck won't start after Ax15 Swap...

[Bonkers]

1988 - 4.0L-Ba10-4x4...

 

I have a new Luk LFW194 flywheel installed. Was my daily

before the swap. When old CPS did not work, replaced with

new one - no change. Motor cranks and I have fuel and spark.

 

The only thing odd about this swap (besides the never ending

array of headaches) is that the strap I had holding the motor

level broke the first day - the motor sat tilted back for the

three weeks its taken to put in the new Ax15.

 

If I have to dig back into the transmission I'm calling it

quits on repair/fit and leaving her sit until I'm ready for the

rebuild. I'm hoping theres something obvious I missed, but I

don't see any random plugs sitting loose, and from what ive

read/been told there are no other switches/sensors besides the

CPS that would prevent it from starting...

 

Any ideas? I have a parts run Sat morning, but I have all

afternoon to pick at issues....

[86FUBAR]

Just a shot in the dark but since you said the motor tilted back maby check for a pinched metal fuel line ? Also did you try starting fluid and see if it pops on that ?

Also is there perhaps a different CPS for the ba10 and the ax15 ?

[87MJTIM]

Also is there perhaps a different CPS for the ba10 and the ax15 ?

The CPS should go with engine not the trans

[Eagle]

You have a mystery. An internal combustion engine only needs three things to run: fuel, air, and spark. You report that you have fuel and spark, and it's unlikely that changing the transmission could affect the air intake system, so ... what are we missing?

 

Are you certain that the flywheel you bought is for the year of your truck? The "tone ring" (for lack of a better term) is different for the Renix system than for the Chrysler HO system. Likewise the CPS is different. You have to have the correct flywheel, and then the CPS has to match the flywheel. However, if you didn't have all that correct, it's unlikely you would have spark -- or injection, since both are controlled by the CPS.

 

Did you do ANYTHING else while you were working on it? Did you by any chance have the distributor out? Where are you checking for spark, and where are you checking for fuel delivery?

[gte636p]

Are you certain that the flywheel you bought is for the year of your truck? The "tone ring" (for lack of a better term) is different for the Renix system than for the Chrysler HO system. Likewise the CPS is different. You have to have the correct flywheel, and then the CPS has to match the flywheel. However, if you didn't have all that correct, it's unlikely you would have spark -- or injection, since both are controlled by the CPS.

 

 

x2

 

it almost got me on my XJ when I was sent a wrong part, but put in the right box.  The timing gates are different.  Given the pickup in the distributor (H.O.) I don't know if it would even send a spark to the plugs. 

[Bonkers]

An internal combustion engine only needs three things

to run: fuel, air, and spark.

... *sigh*... yeah, but without compression and timing...

 

Are you certain that the flywheel you bought is for the year

of your truck?

No... I am certain I bought the right part, and Luk has a

great reputation for sending the right part... It looks

like the right part... but at the end of the day (as it

stands while typing this) its certainly looking like I have

the wrong flywheel.

 

Did you do ANYTHING else while you were working on it?

Well I tried very hard not to touch anything else since this

was my first major repair... ever... (which is why it took

over a month too.) Thats why I am asking - if there are any

plugs I missed. Saddly the In-Between Owner did a lot of

backyard repairs (I think he did a bastardised CAD upgrade at

some point. All the vacuum lines were cut and re-routed. There

are wires dangling everywhere BEFORE I started... ect...) so

there may be a wire I hit/pulled that I did not even notice.

 

The only thing that did not go to plan was the motor hangin

back when the strap broke. It sat at an odd angle for weeks while

I tried to get trans swapped. can't imagine the motor would

care, but at the same time the fan was pressed against the hood

so I'm wondering if 86FUBAR is correct - maybe I pinched/cut

something between the firewall...

 

I was running for parts all day today - I'll do a more thorough

search tomorrow when the sun comes up.

 

Thanks again guys...

[sloride]

Check your ground straps, one to fire wall?

[Eagle]

Let's go back to basics: Fuel, Air, and Spark.

 

1. You brought up compression in response to my previous post. Have you checked the compression? If so, what is it?

 

2. You posted that you have fuel, but where do you have fuel, and how much? Has this engine run (for you) before? If you have fuel at the fuel rail, what's the pressure? Have you pulled an injector (or two or three) to be certain it's squirting? Have you tried starting it by dribbling a little gasoline directly down the throttle body? (NOT while cranking -- dribble first, move gasline container away, THEN crank)

 

3. Spark. You posted that you have spark. Where -- at the coil, or at the spark plugs? Have you removed a spark plug and grounded it to the block to verify that the plugs are firing? And then, of course, there's timing. Have you confirmed that the spark for the #1 cylinder occurs when the #1 cylinder is at top-dead-center (TDC) ... on its compression stroke?

[Bonkers]

Sorry, i was just commenting that fuel / air

spark arent enough to run a motor. The truck

ran fine beforehand. If the trans didnt give

out on me it would still be my daily.

 

Fuel - the plugs are wet after cranking. Ive

squirting starting fluid down the TB with no

result.

 

Spark - i had spark at the plug, but when i

put in new Crank sensor the spark went away.

Now i cannot get spark on either crank sensor.

 

New development - when i opened the distibutor

there was a layer of orange... liquid on the cam

sensor. So i ordered a new one. If that doesnt

work i think its fair to say Luk might have sent

me a bad flywheel...

[xjrev10]

Didn't happen to have a picture of the flywheel you installed....?

 

Did you compare it to the old one?

 

When I did my nv3550 swap in my MJ, I bought all the clutch stuff and flywheel for a 97 XJ. I was in the same place as you as the truck would not run. So I been there. Frustrating as hell.

[teamsmith]

As previously suggested I would pop the intake tube off and spray carb cleaner or similar to see if it will start. If it doesn't start and you're sure its sparking and timed, then it's your cps or flywheel.

[Bonkers]

... apparently I need to disassemble the distributor

to replace the pickup... Thats beyond my time and

talent...

 

I'm gonna tinker a bit more, but if she doesnt run by

sunday I will have to put her to pasture for a few

years until I am ready for the resto.

 

This so called "easy, bolt-on" swap has been nothing

but a LONG series of headaches and disappointments.

Nothing fits the way its supposed to, there have been

several permanet modifications, and now the truck

doesnt even run because of it. Would have been better

off to just stick with the dying Ba10...

 

I appreciate the help guys, I really do, but I think

I'm done now...

[teamsmith]

I do understand the frustrations from a swap. I had never changed the oil in a car before attempting an engine swap last february; I could have bought a few brand new trucks with the number of man hours spent on that. 

 

I do not understand how your timing was effected by the transmission swap; I thought the flywheel only went on one way. I do know how frustrating it is but you're so close if all you have to do is set the timing. There are a few good writeups about it on this site. 

[87MJTIM]

:hmm: I'm confused.  There must be something missing.

 

In the first post, you stated that you were swapping a BA10 for an AX15.  You changed flywheels.  I just did this same swap on my 87 and kept the original flywheel and CPS.  These two are engine specific, not trans specific.

 

The swap took a few weeks to complete. Not unusual.  

 

When you bolted everything back together, the engine would not start.  It was running before you started.

 

In post #9, you state that you opened the dizzy and found "a layer of orange liquid."  Is it oil?  Do you have a coolant leak somewhere?

 

While you had it apart for the swap, did you "work" on anything in the engine?  I am guilty of doing "investigative" repairs:  "What is this?...Oops...Oh, shoot!...Where did that piece go?....How does this fit back on there?"

 

I cannot see how a trans swap would have caused the dizzy to break.  There must be more happening that we don't know. 

 

You say the PO hacked up the wiring.  I am at a disadvantage.  I am the only owner.  My wiring has not been hacked up.

 

Do you still have the old flywheel?  Can you reinstall it?  I know it will require dropping the trans and reinstalling.  :doh:

 

Something else is wrong than just the trans swap.

[Bonkers]

In the first post, you stated that you were swapping

a BA10 for an AX15...

Yes, I bought a LFW193 for the swap, but then discovered

it was the wrong one, so I went into storage and pulled the

LFW194 I had saved for the Eliminator (whose Ba10 is still

running strong so I figured I would just replace the clutch

on that one since it was so cheap.) They're both 88's.

 

The swap took a few weeks to complete. Not unusual.

Sunday begins week #7. My lift is beginning to rust being

outside for so long. I simply don't have another 6 weeks

to try again at this point.  

 

It was running before you started.

Correct. The only issue with it being my daily driver was

the dying slave cylinder.

 

Do you have a coolant leak somewhere?

Its not coolant. I'm thinking it could have been stagnant,

rusty water which is why i initially decided to swap the

CmPS. I still don't know what it is, but I'm sure working on

it in the rain/midnight humidity isnt helping.

 

While you had it apart for the swap, did you "work"

on anything in the engine?

Nothing. Was planning an oil change once I was done, but

the birds nest of cut/sodered wires and vacuum lines made

me decided against snooping. I have three wires off the

Ax15 which apparently have no home now, and at least five

plugs dangling under the motor that I didnt unhook.

 

I cannot see how a trans swap would have caused the

dizzy to break.

Me neither, but so far (according to the forums) somehow

this swap causes both the CPS and the CmPS to magically

stop working... for whatever reason...

 

You say the PO hacked up the wiring.

Its so bad that I plan on buying a new harness when it

comes time to do the resto. I did a cluster swap 12yrs

ago when I had it, he put in another, and when the

gauges didnt work on the new one, he cut wires and

installed a stand-alone gauge system. I found the

vacuum lines that came out of the Ba10 balled up under

the motor mounts completely disconnected, just sitting

there... like I said... nightmare...

 

Do you still have the old flywheel?  Can you reinstall it?

I do, but its been sitting out in my yard for the past

five weeks. But if I'm gonna go through all the headache

of pulling the trans again I'll just buy another flywheel

to install.

 

Something else is wrong than just the trans swap.

I'm going to search non-cps issues this weekend and hope theres

a second issue that developed because the truck was sitting

out in a massive amount of rain, disassembled. But realistically

its looking more and more like a bad flywheel, which... of

course it would HAVE to be the flywheel...

 

Another issue that I discovered last night is that the

driveshaft no longer fits not either. Along with the

forced crossmember mount its almost as though this Ax15

is 0.5-1.0 inches longer than the Ba10. I don't know how

that matters, but its bolted to the motor flush which

means everything else "should" line up perfectly...

[teamsmith]

You say you have plugs hanging under the engine that are not hooked up. Did you reconnect the o2 sensor, which had to be disco'd to remove the exhaust downpipe? I would think that it would still turnover even without a sensor but it's a thought. 

 

Are your starter wires tight? No chance you frayed or cut into the ground wire on the starter when removing/replacing it? 

[Bonkers]

No sensor on the downpipe.

 

The starter seems tight, and motor

does spin.

[teamsmith]

Got it. I forgot that the bung is on the renix header. How much gas is in the tank? Could have built up with condensation while sitting for 6 weeks. Did you ever try spraying a starter fluid in the intake while cranking to see if it would turn over? 

[Megadan]

The AX15 mount location IS further back than the BA10.  I did the swap a couple of years ago and I had to track down a crossmember for the trans, and ithe crossmember moves back to the rear holes that are already present in the frame.  

As far as your driveshaft not fitting, that's strange to me as I reused both front and rear shafts on mine with no problem.

[gte636p]

I forget how tight the wiring harness is, but did the grounds on the side of the block somehow pull out with it hanging for a while?  Spent a few hours tracking that down myself...if anything i would try to make sure the electrical was right before swapping out transmissions again.

[Bonkers]

Still not getting spark.

 

Spent the entire weekend running leads. I am now 100%

sure I installed the part Luk said was a LFW194 flywheel.

I am 100% sure the CPS is the correct part AND is

functioning properly AND is mounted correctly.

 

The ground to the block looks and feels healthy, and it

draws a current across it.

 

I have run down every unplugged connection (both vacuum

and electrical) and did not find one out of place.

 

I have fuel (did not measure pressure) and starter. Sraying

fresh starter fluid down the TB produced no results.

 

Now next set of questions:

What engine fuses do I need to check and where are they?

I know where the interior fuses are and the engine relays,

but no clue about engine fuses.

 

Everything is now pointing to the CmPS - is there an easy

way of swapping/testing this out or will I need to pull the

distributor and injectors like the JP forums outline?

 

-----------------------------------------------

 

On the driveshaft - I measured out both the old trans, yoke

and shaft and they are within millimeters of each other, but

the shaft will not fit on the diff with the yoke bottomed

out on the TC. The Ax15 did not fit the crossmember nicely,

it had to be forced. When I jack the rear up to install it

later this week the shaft will be installed, but it will be

under enormous pressure once the truck is sitting on the

ground...

[Crash]

The actual CPS (not Crank sensor. correct designation for crank sensor is CKP but most do not use that) is in the dizzy. I believe that I have seen some people swap it. But, it typically goes with the dizzy. 

Easy to swap the dizzy. From my understanding, and having my heep run without the CPS connected, I do not think it really makes much difference. 

 

I would definitely consider indexing your dizzy, making sure that the wires are correct, coil good and producing a proper spark. Seems like the spark is not proper if using starter fluid is not doing anything. 

[MancheKid86]

bonkers,how did you verify you have the correct fly wheel?

did you visually look at it? or just go by what they said

 

your fly wheel is the only variable that has changed besides the transmission-(which doesnt matter for spark)

if you have the ho fly wheel it, the cps will still fluctuate on a multimeter, it is still detects the gaps in the fly wheel

 

 

it only makes sense that the new fly wheel may not be the one you think it is

 pulling the trans should take two hours going at a steady pace so its not too much of a setback

i think you should verify visually that its the correct one, you can pull your CKS and rubber grommet of and peek through the top to make sure it has the correct shutter spacing

 

 

this is a HO fly wheel

 

 

 

and this is the correct renix fly wheel

 

 

 

 

 

 

 

also, you said you forced the transmission into the cross member?

 

you do realise the AX-15 has its own cross member and you cannot use the ba10 cross member right?
 

the ax 15 x member mounts about 1-1.5" further back.

 

 

if your drive shaft doesnt fit and is bottomed out, DO NOT PUT A PRELOAD ON IT,

you will blow your transfercase apart,

 

Are you doing a 4wd conversion? that would make the drive shaft too long

 

let us know what you find out,

i don't think its a dizzy/timing issue, my dizzy bearing was almost completely gone and it still ran and produced spark

[87MJTIM]

I think MancheKid86 is on to something.  If the only change was the fiywheel and the truck no long starts, that should be the place to look at first.

 

You can remove the starter and get a better look at the FW, then looking through the CPS opening.  

 

I swapped my BA10 for an AX15 three months ago.  I kept the original flywheel.  I had not problems starting and running the truck.

[metrictonner]

Boy howdy.  Sensor schmensor.  Sensors are very seldom the problem no matter what they say.  Not only don't they generally fail but if they do the computer has defaults to replace bad sensor readings.  More than likely the new junk they sell as sensors is what is bad.  Yellow stuff in the distributor, now there's a new one.  I've replaced many a flywheel and NEVER have I got yellow stuff in the distributor.  Oil isn't yellow, coolant isn't yellow,  gas isn't yellow,  block rot isn't yellow (Bars, Prestone, STP, etc).  When you take a plug wire in your hand and press your hand to the block and have someone crank the engine do you get a 40,000 volt jolt?  When you press the fuel pressure depressurize valve on the fuel rail do you get a face full of gas?  When you remove the rubber air thingy attached to your thottle body does your throttle body suck?  Thats how to test for spark, fuel and air.  Because of the asymetrical bolt pattern on the flywheel, they are impossible to install improperly on the crank.  The BA tranny has no neutral lockout, I don't know about the AX.  The 4.0 tilts on the front engine mount just fine.  In fact you have to tilt it for the bell housing to clear the body tranny tunnel if you pull the tranny out from underneath the truck.  You don't buy a NEW distributor, they only have rebuilt Renix ones.  Sometimes you get them with the drive gear reinstalled 180 degrees off and since the gear has an odd number of teeth you end up with a distributor about 7 degrees out of wack causing a worse problem then you started out with.  If you feel uncomforable pulling a little drive gear pin then I would stay away from any kind of distributor fix.  You have a shifter, reverse light switch, engine speed sensor,  a breather tube, clutch lines coming off the tranny itself (BA).  The transfer case has a breather, vacuum actuators and a shifter. Nothing should cause a no start condition.  All of my LUK flywheels are LFW194's.  LUK clutch kits, with their superior throwout bearings, are 01-035's.

 

My guess is you got kids.  Ask them what they did under the hood while you were under the truck.

 

I must admit that the engine speed sensor, referred to as the CPS on this board (actually the distributor sync sensor determines crank position), seems like a likely candidate for problems.  While the distributor sync sensor input problems can be defaulted away the engine speed sensor is required to determine when 300 rpm is reached.  If your battery\starter never pumps out enough juice for a 300 rpm startup, Renix says you won't start, sorry.  So while you may be getting air, spark and fuel to the injectors, the ECU may not be actuating your injectors because of low starting RPM.  Then of course you may have old, filthy, open ECU connector contacts but hey, you have spark, right?