Engine tapping

Topic: Engine tapping (Read 1489 times) previous topic - next topic

Engine tapping

October 20, 2008, 12:53:16 AM

I'm here for ideas but I think we have our course of action already set. We started the new motor yesterday and after fighting a ground issue with the transmission's computer (made check engine light flash rapidly), everything runs perfect with exception of loud exhaust and a tapping that continues to come from the motor, even after warmed up. Oil pressure reads 70psi cold, ~30 at idle when warm and all rockers get oil fed to them as was tested. The clearances on the piston to bore on the forged pistons are .0045 so the noise, even if cold, shouldn't be this for the volume level the tapping is at. The engine is smooth and during the 6 month long build, everything was checked three to five times to make sure everything was right when putting the motor together. We believe that this sound may be exhaust leak at the lower part of the headers but I've never heard anything this pr0nounced. We used hose to listen to different areas and around the exhaust is where it seems to be originating but it certainly sounds like dry lifters (perhaps a bit louder). The lifters have like 600 miles on them and ran quiet in the first motor so I don't think they are at fault for any sloppy valve train.

Is this a common thing to hear with an exhaust leak at the heads?

Also, the initial DRY (other than oil on the walls after assembly) compression test on the engine ranged from 120 to 180psi, before it was even run. Each ring was fit to its specific bore. We shot oil in one, through the adapter for the compression tester since its a paint to get the thing in/out with the headers in the way so we're unsure how much made it in, and the compression went up 10 so I assume that cylinder (went from 130 to 140psi) is rings. This isn't uncommon for a new motor, is it not? We'll be retesting the engine next weekend after we work out a few quirks. Exhaust leak cannot be 100% guaranteed fixed on drivers side due to a motor mount issue. The engine smoked a little for about 5 minutes after the first start (well 4th, it wouldn't stay running the first few), but cleared up so the pistons sure seemed to expand and rings began their seating process.

Edit:
We did not have any sort of problem on the last motor other than a crack letting water in the oil. The entire valve train was quiet with the gt40 heads and stock exhaust manifolds/exhaust. The gt40p heads are using the same rockers and thankfully, it can use the same length of pushrods with a couple needing shims at the rear of the motor. The 1/2-3/4 turn test after pushrod stops spinning trick worked quite well on the last engine and it shouldn't be any different on the new one. On a related note, the cooling system holds pressure and doesn't leak in this engine. I got a good machinist this time around.

Engine tapping

Reply #1 – October 20, 2008, 11:42:59 PM

if your running the same lifters, they may be collapsed from being in your other engine. then when you tightened your rockers, you tightened them too much because your lifters were not pumped up. after running your engine for a bit, try loosening up your rockers and retightening them. kind of a pain to do on a fuel injected motor, but its a good idea to retighten them shortly after running a rebuilt motor anyways, problems or not.

Engine tapping

Reply #2 – October 21, 2008, 12:59:53 AM

We're going to do that since we need to retorque the lower intake and pull out a broken bolt in the lower intake (bolt was apparently on its last leg). This doesn't make much sense in regards to them being too tight though as that would just hang the valves open. We have already checked for such foul play in the valvetrain last Friday. It will be rechecked since the motor has a few minutes on it. Anyways, it'll be a tweaking weekend for sure as I still need to find out why my solenoid ground for the TCS is causing the dash's check engine light to continuously flicker, along with the light on the TCS itself. Lastly, we still need to do the smaller tasks like recharging the AC and wire management. I hope it is fair weather this weekend.

Engine tapping

Reply #3 – October 21, 2008, 11:58:15 PM

Are you sure the headers are on tight? I had a hell of a ticking noise untill I re-tightened the header bolts on the down after I first started the engine. Since then no noise... Are you running the FMS stainless headers for the GT40P heads? That's what I'm running.

Engine tapping

Reply #4 – October 26, 2008, 11:30:07 PM

turns out a lot of the lifters were seized temporarily. Running the motor broke them all free and they became loose. After retorquing them all, it sounds like one last one ended up breaking free. We need to pull the valve covers one last time to quiet that one down. The lifters have a little over 500 miles on them I believe, they are Comp Cams hydraulics. They were in the last motor that had a mixing of water and oil, after being pulled out they sat in a tub of oil until being installed in this engine. I doubt their short life in the other engine did any harm, but I won't rule it out.

On another note, the motor runs great, as does the 4r70w behind it. I know the transmission is young, but does that thing shift hard - I'm not 100% this is normal without any mods done to it. I will talk with Baumann Engineering tomorrow. It seems to be stalling around 2500, great area for this motor.

Now to find a mass air ecu...

Engine tapping

Reply #5 – October 27, 2008, 10:43:54 AM

Hopefully the lifters lube up and quiet down for ya.

Is the 4R70W shifting hard all the time? The 4R70W in my 95 shifts really, really smooth unless my foot is to the floor. Then I can feel the shift a little bit. If you can feel it shift in normal driving (like an AOD) then something is not quite right. Did you put a shift kit in? That could have firmed up the shifts...

Engine tapping

Reply #6 – October 27, 2008, 01:58:02 PM

Quote from: thunderjet302;240514

Hopefully the lifters lube up and quiet down for ya.

Is the 4R70W shifting hard all the time? The 4R70W in my 95 shifts really, really smooth unless my foot is to the floor. Then I can feel the shift a little bit. If you can feel it shift in normal driving (like an AOD) then something is not quite right. Did you put a shift kit in? That could have firmed up the shifts...

Baumann believes it is the base configuration file I used. After looking at the line pressure curve, the one I'm using seems to have quite high pressure down low compared to some of the other configuration files. I was told to try the base ZephyrW5 calibration file and go from there.

Going from park into drive is about normal but into reverse is very harsh. All my shifts are similar to going into reverse - the car lunges and the rpm's drop from ~1000 in park to ~700 in either forward or reverse gears. I still need to perfect the idle level also so I'm not too worried. I will say though, driving the car yesterday was the first time in years that it made me smile. Once it hits 2500rpm's, the ride remains smooth like I'm not going anywhere, yet the speedometer climbs rapidly - uphill. The quick response of the 4r70w is great too - it just downshifts too early on as I feel I'm already accelerating too quickly, yet I only have 2v coming from the TPS. In the middle of what used to seem like WOT on the SO motor, the tranny upshifts on this one. It'll just take some getting used to and tweaking - after all, it actually should shift if I'm not really getting on it.

Lastly, the real time monitoring is nice to have. I have an Asus R2Hv that I have plugged into the TCS. My biggest complaint is the second delay between mechanical response and what I see in the software. I'm not sure how accurate the temperature reading is, but according to the weather, with "cold" fluid, it seems pretty accurate.

Engine tapping

Reply #7 – October 28, 2008, 01:33:01 PM

Should idle alittle bit lower then that I would think. I think idle is around 600 rpm's for a stock 5.0 s.o.

Engine tapping

Reply #8 – October 28, 2008, 08:49:17 PM

It's fine - we haven't messed with it yet. Fixing some wiring issues with the car steadied out the idle so now we need to do the final touches including setting the idle. I've got some new spark plug wires since the headers almost completely melted through the short Napa ones I have on there (two keep moving back towards the header tubes on their own), along with the Ford Racing aluminum wire retainer things they sell under the name of "billet spark plug wire loom". It should work well at keeping the wires where they need to be. Also need to replace the 2 year old transmission mount this weekend but that'll only take 10 minutes. As long as weather permits, the car will be finished other than putting the interior back together.

Here's a good one - what course of action would anyone take if opening the car door when the light dimmer switch is in the "on" position causes the headlights to turn off, yet closing the doors causes them to turn off? With the dimmer "off/not in the upmost position", the headlights would remain off. The lights turning on and off would blow the 15A fuse in a minute. There was sure a strange solution. The problem is the lights' relays were not hooked up to 12v (had one last wire to hookup to the alternator). How they turned on prior to this is beyond me. The relays only use the stock light switch to be their signal wire. The world will never know.

Engine tapping

Reply #9 – October 29, 2008, 11:19:08 AM

If you don't mind me asking how much did the 4R70W conversion run? I keep going back and forth between that (I love the 4R70W in the 95) or building up my AOD. I know I can do my AOD the way I want it for between $2000-2300. I'm wondering if the 4R70W can compete on price/ease of instalation....

Engine tapping

Reply #10 – October 29, 2008, 10:14:07 PM

I spent $450 on the '03 3.8 motor/transmission combo with 13k miles. All crevices were still clean with factory writing and red transmission fluid. $550 into the computer/harness.

The swap only required cutting, bending, and welding the crossmember, along with extending the slot to move the mount back further. I had 4 wires to solder at the original harness going to the AOD, along with 4 wires going to the ECU. The cooler lines thread right in. I had to hookup the speedometer sensor to the outut shaft and swap the output shaft from the AOD onto the 4r70w. The driveshaft did not need to be shortened.

The stock shifter works just fine and can be adjusted to use the exact same locking gates as the aod - they line up with the gears in the 4r70w (I just need to replace "D" with "2"). We used the stock stall converter which is rated to stall at 2200. We're stalling around 2500-2600 on this motor. I have not touched the valve body but will do at a minimum the jmod after I get some time to relax away from working on the car every weekend. I also have a large transmission cooler to bolt in.

After hooking it all up, we just put the car in the run position, plugged in the computer, and threw a stock calibration on the transmission. Everything worked well and the simple monitoring stats on screen while driving make it easy to see what's going on with the transmission.

I think I've seen like $300-400 in upgrades that are supposedly capable of making these things handle over 500hp at the rear wheels. I'm sure at some point I'll do these mods just for the hell of it, even if this car will likely never see the track.

Edit:
The biggest pain we had during installation was the dimple on the pan - it made using the transmission jack a bit more difficult.

Engine tapping

Reply #11 – October 30, 2008, 04:59:54 PM

Well that's about half the price of the built up AOD I want

When you say the shifter lined up fine do you mean the floor shift of column shift? I'm hoping you mean column shift....

The only problem I have is finding a good 4R70W. The only ones I can find are from 94-97 3.8 T-birds or Cougars which: 1. are not as good as the 98 and up 4R70Ws for durability and 2. they have over 100,000 miles on them. I never seem to see any 99 and up 3.8 Mustangs in the yards near me.....

Engine tapping

Reply #12 – October 31, 2008, 08:49:53 PM

Floor shift. It shouldn't be any different as you'd use the same cable already on the car. The 4r70w's gear points appear to be in the exact same place as the AOD. We ended up having to push the linkage all the way one direction (I think towards the transmission) and tightening it down in order to get the perfect shifter adjustment - it was quite ease to adjust due to this.

I really got lucky stumbling upon this - I haven't had any luck finding a 99+ 4r70w until I stumbled upon this low mileage one. Of course, I had to c00ch it up immediately. I wasn't planning on going to this transmission so soon as I already had a new AOD on hand but it's hard to resist the potential of these things.