2.9L Heads

[SuperRob]

Just wondering if theres a difference between the left side and right side heads on a 2.9l? I'm aware that the head gaskets are different, but cant seem to identify any differences between the 2 actual heads....any help is appreciated!

[MAKG]

Nope, no difference.

One is just the other rotated 180 deg. Coolant flow is regulated by the head gaskets (that's why they are different -- the difference is that the small coolant holes go in front).

They even crack in the same place (#1 and #6, right through the Ford logo).

[SuperRob]

Thanks MAKG.

But I cant see this Ford logo that you talk about. I'm going to keep cleaning them up, but can you explain a little more exactly where it is?

Much appreciated!

[MAKG]

On my (former) 86TM castings, it was located directly on top of #1 and #6, near the rocker pedestal. The later castings might differ.

[SuperRob]

I found the logo, but on all 4 heads that I have its located between the valves and the middle pedestal over cylinders 2 and 5.

Tomorrow I'll get the exhaust manifolds all off and spray them with that dye penetrant that I have. I'll find the crack one way or another! Although I wasnt planning on having to take the valves out.

[SuperRob]

Just an update on the head replacement battle.

I had to drill out some exhaust manifold bolts on the replacement heads....and I had to do it freehand. Overall I did a pretty decent job, but pretty decent doesnt count for much when you try to bolt everything together and end up with one bolt that just doesnt want to thread.

SHIT!

[MAKG]

It's a flange. Can you get a nut behind it?

Or just tap it to the next size?

[SuperRob]

I was thinking about using a nut too. Cant go to a bigger tap because then I'd have to drill out the bolthole in the manifold...and its about 2.5 inches long.

Will keep you updated.

[SuperRob]

So I bolted it with a nut on the other end. Made'r work.

But I get out there and figure I best cycle the engine over by hand to make sure theres no cracks in the cylinder walls. And low and behold in #3 I noticed some ugly marks....not like usual scoring though, very irregular and diagonal. I just tested it with dye penetrant. Appears that its not a crack.

Now I'm running a tap thru the head bolt holes and the intake manifold holes to make sure theres nothing in there to screw with me.

I sorta hope that somewehere along the way it gets WAY screwed so I can scrap the project and find a 302.

Back to the battle....and Brooks and Dunn

[SuperRob]

Got one head totally on and torqued. The other head is on, I'm halfway through the final step (90 degree turn past 55 ft-lbs) and I broke my damn torx driver. And theres nowhere open to get another one till tomorrrow...so I hope that its not going to be an issue having half of the head torqued fully until morning. We'll see though!

[SuperRob]

Ok...well everything is done now up to the fuel rail. Tomorrow morning I have to get the distributor roughly timed (at least withing the 180 degrees!!!) and put the upper plenum on and I reckon it'll take about 1.5 hours or so.

Wish me luck....(shit I hope leaving that head halfway torques overnite didnt screw me over!)

[MAKG]

A trick for rough-timing a 2.9L is to put the crank at 10 deg BTDC on the compression stroke (when both #1 valves are completely closed -- which you can see if the passenger side valve cover is off), pull the SPOUT plug out, turn the key on, connect a timing light and hold the trigger down, and turn the distributor until it fires. You could also use a spark tester in place of the timing light.

The Hall effect sensor is effectively a switch, and it will work at arbitrarily low RPM.

[SuperRob]

Ok. Here goes.

So I got everything put back together. I have a question regarding 2 ground straps though. Theres one on the harness that plugs into the distributor, I connected it to the back of the upper intake plenum where the AC hose bolts on. Then theres another one off the back of the drivers side head. I dont remember where it bolts to, so I connected it to another point on the intake plenum. Just arbitrarily chose a mounting bolt that bolts the 2 halves of the intake together and stuck the ground there....but I'm pretty sure thats not the right spot.

My battery is dead, dont know why. BUT I did try to get it to run off of a friends car, it turned over (although a little slowly, but it should have been enough to hear something!) but wouldnt fire for the life of me. I checked for spark, and have it at LEAST to the number5 plug (thats the wire I tested it on.) I have fuel pressure, (Tested by relieving all pressure from the fuel rail by way of the schrader valve and then repressurizing it.)

Long and short, she still dont go.

If anyone can let me know that I got those ground straps right I'd appreciate it. Also if you can think of anything thats held you back before when in this kind of spot I'd love the advice.

I got the crank to 10 Degrees BTDC on compression stroke, (verified compression stroke by the ol' finger in the hole method) and then checked on the timing marks. Then I put the distributor in so that when the rotor spun on the way in it lined up with #1 plug) Then I double checked the firing order of the plug wires, and theyre all right.

Tomorrow or Tuesday (most likely Tuesday, I have a paper to write tomorrow) I"ll go back and play a little more.

Thanks for any ideas!

[IMenriched]

[QUOTE=SuperRob;3167]Ok. Here goes.

So I got everything put back together. I have a question regarding 2 ground straps though. Theres one on the harness that plugs into the distributor, I connected it to the back of the upper intake plenum where the AC hose bolts on. Then theres another one off the back of the drivers side head. I dont remember where it bolts to, so I connected it to another point on the intake plenum. Just arbitrarily chose a mounting bolt that bolts the 2 halves of the intake together and stuck the ground there....but I'm pretty sure thats not the right spot.

QUOTE]


I'm pretty sure the other ground strap (small braided thing) goes to the windsheild wiper motor.
there may be a onother ground on the bellhouseing (passagerside) bolt to the cab ...double check that....but I doubt if you took it off for your head job.

good luck...hope this helps

[MAKG]

2.9Ls have ONE ground strap to the upper intake. It goes on the driver's side near center. There should be NO other ground straps going there. Both heads have and need grounds. One is a strap (driver's side) and the other is an orange wire coming out of a wiring harness. Leaving either of these out will cause driveability problems.

[SuperRob]

MAKG, Can you confirm that the braided strap from the drivers side head (at the back) gets grounded to a wiper motor?

The orange ground you talk about I believe is the one I found in that wiring harness. Off the distributor....shared with the injectors.

[MAKG]

It certainly goes NEAR there, but I always thought it went to the firewall.

I never disconnected that one.

[SuperRob]

Well, I used to OWN my truck...but apparently these days I'm being :owned: BY my truck, and it doesnt feel very good at all.

That braided ground strap looks like the only place it can reach is that wiper motor ground bolt. However in the 4 years I've owned this truck its never been attached there, and I definitly didnt take it OFF of there when I took things apart this time. I'm just positive that its been attached to the back of the upper intake plenum this whole time, and it worked before, so it should work again.

The upper intake itself has continuity with the negative post on the battery, so as far as I'm concerned...a ground is a ground is a ground right?

Next thing, That orange wire you were talking about. I found'er alright. But for the life of me I cant see where it would bolt onto the drivers side head!!! Its reasonably short, which implies that it goes to the back of the head, but I didnt disconnect anything from the back of that head when I took the original off! I'm looking at the original from that side and theres nowhere that I'd have undone it from with the exception of one bolt hole that still has the bolt frozen in it. Clearly I didnt take it out! Where else could it go?

Next thing. With the key on, if I turn the distributor I hear a clicking sound like a relay but they come from 2 spots. One from the power distribution box (passenger side fender) and the other from the distributor area (but I cant tell where) sometimes one of these clicks is followed by what sounds like a pump priming up (but again I cant tell where it is due to background noise and trying to manipulate the distributor and listening all over the place all at once.) Does this sound normal to you guys? Should I be hearing these noises or should I be preparing to look for bad wires? WHATS GOIN ON?!?!?! I hate this! Trouble shooting SUCKS why couldnt it just work right the first time for me!

Thanks All

[MAKG]

Remember, the heads are identical. So if you want to see where the holes in the back of the passenger side head are, take a good look at the FRONT of the driver's side head.

In principle, the arc firing between the rotor and dist cap will make a noise, but I'd expect it to be too faint to hear. Is this a new dist cap and rotor? Are all the plug wires pushed ALL the way on? The fuel pump relay is in the PD box, and I suspect you're hearing that as well as the fuel pump.

[SuperRob]

Remember, the heads are identical. So if you want to see where the holes in the back of the passenger side head are, take a good look at the FRONT of the driver's side head.

Thats exactly what I did. I also looked at the exact head that I took off of the passenger side and like I described, found only one possible location to bolt it to, but that I had never taken the bolt out of there, so it couldnt have been connected to that spot.

In principle, the arc firing between the rotor and dist cap will make a noise, but I'd expect it to be too faint to hear. Is this a new dist cap and rotor? Are all the plug wires pushed ALL the way on? The fuel pump relay is in the PD box, and I suspect you're hearing that as well as the fuel pump.

I'll double check all the connections there, It'll likely wait till Friday afternoon though, I have a stats test (final) on Friday morning, and it takes priority.

I still dont understand why rotating the distributor would activate the Fuel Pump relay....

Thanks

[MAKG]

The fuel pump relay is supposed to be energized for two seconds after the last ignition event. The two seconds is to prime the fuel system, and the after the last ignition event thing is to keep the pump running while the engine is. It's normal.

[SuperRob]

WOAH!!!

COOOOL!

Thanks. I've got a renewed hope!!!!

Will update on Friday

[SuperRob]

So I'm back to the grind here.....not winning.

I've started a post in the Electrical forum, its more relevant than continuing this one.

Thanks!