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racer88
04-29-2003, 07:08 PM
I need help setting the timing on a 3.8 SC.

I am rebuilding my 3.8 SC, I have the timing marks set, but then how do I set the syncronizer?

Chilton manual says that when you replace the syncronizer to turn the crank to 26 degrees ATDC. then take out the syncronizer and put the new one in.

Can someone explain to me how to set the timing right?

Thanks
Bennie

Aaron Pedroza
04-29-2003, 07:16 PM
no way to adjust timing unless you have and EEC tuner

racer88
04-29-2003, 07:20 PM
I know that there is now way to adjust the timing, I need to set the timing before I can start the engine.

Aaron Pedroza
04-29-2003, 07:28 PM
Sorry, there is a cam ~~~. sensor sychronizing tool, just a piece of plastic to hold it in place while you slide the gear in. You can hold it with your finger while you slide it in but you have to know where to hold it, I guess that's what the tool is for.

Aaron Pedroza
04-29-2003, 07:30 PM
actually, if you're not taking the distributor(or whatever it's called) out then you should be able to just bolt the new one back one without a prob.

racer88
04-29-2003, 07:59 PM
So, then I leave the cam and crank timing set with the marks and then put the syncronizer in? I have the postioning tool, I was just wondering if I have to turn the crank to a certain timing mark before I put the syncronizer in?

racer88
04-29-2003, 08:02 PM
by turning the crank I mean, after I put the timing cover on and put the harmonic balancer on do I then leave the cam/crank timing at 0 degrees or do I turn it to a certain degree before I put in the syncronizer

Aaron Pedroza
04-29-2003, 08:07 PM
Honestly, i have taken off and replaced several cam position sensors and I have never paid attention to crank position, just took off old one and put on new one. I think the only concern is when you take out distributor gear.

racer88
04-29-2003, 08:29 PM
I am doing a complete rebuild on this 3.8. Had 136000 miles and then blew a HG. So I have this thing torn all the way down. I am in the process of putting it back together. Let me know if you have any other ideas.

Aaron Pedroza
04-29-2003, 08:36 PM
Well then set the crank to 26 degrees ATDC then put on the cam sensor tool. When you put the distributor back in, with tool on, have the block(square part of tool) facing up, towards drivers side. It will twist as you insert it and it should face forward, not quite directly forward but about 20 degrees short of that. Only thing you can do wrong is be off by 180 degrees, it won't hurt anything but it just won't start. If it doesn't then try again, my first try was 180 off. When I read this it doesn't sound to clear but let me know if you get it?

racer88
04-29-2003, 08:52 PM
Ok, thanks

beedogg91
04-29-2003, 10:02 PM
after my engine rebuild the cam sensor was put in place about 15 degrees off counter clockwise. it is off so bad that the connector rubbs with the supercharger belt. my car has been missing on start up and bogging so bad on acceleration that it misses and backfires. it will do it for about ten min then clear up. my question is that since the cam sensor is turned wrong, does that throw off my timming? or doesnt it matter?? brian

racer88
04-29-2003, 11:38 PM
I would say that it does make a differance. If the timing is off then the valves are not opening and closing at the right time.
When I took my engine apart, then cam shaft sensor was pointing at the passenger side front tire or down away from the supercharger. Kinda sounds to me like the timing might be off by just a few teeth on the cam. I am used to setting the timing on engines with a distributor in them. This SC engine in new to me.

beedogg91
04-29-2003, 11:55 PM
yea i hope thats what is affecting my performance, cause something sure is. i have the following mods:3inch intake, 70mm tb, 76mm maf, ported inlet plenium, cone filter
10% overdrive
no cats, ported headers, terminator res, no muffs
ported and polished heads, ported lower intake, 3 angle valve job, new pistons, crane cam #206, under drive pulleys, comp valve springs, pushrods, all new sensors, magnacor wires,
255lph fuel pump, 38lb injectors
1800 lentech non locker conv., transgo shift kit 275/40/18 in back.
and it doesnt seem that powerfull. the other day at the track i ran a 14.7@89 :confused: with a 2.0 60foot. my old less modded motor used to get me a 15.0@94mph. my symptoms are if i dont let my motor warm up it will hesitate and missfire really bad. then clare up. i have done everything to fix it, but nothing has worked. i wonder how hard it is to re adjust the cam sensor. brian

racer88
04-30-2003, 12:38 AM
With the cam that you have in the engine, are you sure that you didn't have to change the computer or put in a performance chip? That may be the problem or it might be in the timing. I think that the stock computer might show a problem if you go with to much cam.

Aaron Pedroza
04-30-2003, 10:39 AM
Odds are that the cam sensor is way off. You say your car runs bad for a while then seems to run fine. Well that sounds like it is kind of eliminating the cam sensor and guessing on it's own, just like when it goes out. Another thing it will do is synch your fuel pump with engine, no sure exactly what it does but I know it has something to do with it. I would reset cam sensor and your startup and driving at first should clear up. I had some clearance problems too, it will be ablout the same when you have it right but you will just have to twist it out of the way.

racer88
04-30-2003, 02:12 PM
Brian

I found a diagram and instructions on how to install the syncronizer. I can scan them into my computer and email them to you. It might help get the timing set up right.

beedogg91
04-30-2003, 02:46 PM
thanx guys for all your help. i used to post on here for years, lately though i have been so busy with college that i have kind of fadded away from this board. im glad im back, you guys made me remember how valuable this board really is.
aaron: well you say that it shouldnt really be turned out of the way too much. well then how can i know that it is in a wrong position?? i will take a couple pics of it and maybe that would help. it just really looks like it is turned dirrerent from before, i can remember getting the connector off of it before the engine build with no problems. the way it sits now i have to mess with the sc belt tensionor to get it out of the way just to disconnect the harness. i guess i should just buy a new one also, it was one of the only sensors i didnt replace when i changed the motor. also a week ago i had to splice in a new wire on the cam sensor harness because the sc belt had worn a hole in one of the wires. so i cut it out and put another in its place and then soddered it. so hopefully that part is fixed. i hope that sensor doesnt run on resitance because im sure the resistance has changed by me splicing in a new slightly larger wire.
racer88: i have the repair book on this car so if it is the same diagram as the one i got u dont have to send it. thanx alot though man.
can you repostition the cam sensor and all the other stuff below it pretty easilly or what. i think my friend has the syncro tool ill have to check with him. i hope this is what it is because i expected alot more out of this motor. brian

Aaron Pedroza
04-30-2003, 02:56 PM
Mine did same thing, wore some wires, but I just taped em' off and rotated the cam sensor a little out of the way. I also went with the steel pulleys and I think that might have change the angle of the belt to bring it closer anyway.

racer88
04-30-2003, 03:23 PM
Brian

Here is what the last paragraph says:

Caution: If the camshaft sensor electrical connector is not positioned properly (contacting the air conditioning bracket or forward of the supercharger drive belt), do not reposition the connector by rotating the syncronizer base. Remove the syncronizer and repeat teh installation procedure.

That came from Haynes Repair Manual 1989-1997 Thunderbird

I have the Chilton manual for the same years and it doesn't say that.

Sometimes I think that Chilton leaves out a few things.

Bennie

beedogg91
04-30-2003, 04:07 PM
yea i also just put on the steel tensionor pulleys. im starting to wonder if the cam sensor doesnt have to be exactly at a certaint angle, i think as long as it is all put in as one piece and aligned, then it doesnt matter what angle its at. hmmm... im not really sure what i should do. is it possible to put the sensor on the syncronizer wrong?? or something. i guess ill just buy a new cam sensor and see if that helps. then worry about taking out the syncronizer and re aligning it. brian

racer88
04-30-2003, 04:58 PM
I think that I would try to redo the syncronizer first and see what happens, it is always cheaper to do that. If that doesn't work then buy a new sensor.

AlanEdwards
06-05-2005, 12:37 PM
Brian

I found a diagram and instructions on how to install the syncronizer. I can scan them into my computer and email them to you. It might help get the timing set up right.

Brian,

Would you mind sending me that diagram that you describe here, in post block #17? I'm at alan.edwards@romehosting.com. Take care.

Fordrunner38
06-06-2005, 01:37 AM
I need help setting the timing on a 3.8 SC.

I am rebuilding my 3.8 SC, I have the timing marks set, but then how do I set the syncronizer?

Chilton manual says that when you replace the syncronizer to turn the crank to 26 degrees ATDC. then take out the syncronizer and put the new one in.

Can someone explain to me how to set the timing right?

Thanks
Bennie


Hi Bennie my name is Ernie.
As you already know, from your other messages that ther is no way to "set timing" on the 3.8 SC. This is as you probably know is a DIS(Distributorless Ignition System) aka "CoilPak". In any event what you may want to do is do it according to the book since you are doing a complete rebuild. Don't risk damaging any new internal parts since you have time and money invested in this project. 1.) start with setting cylinder no.1 to 26 degrees ATDC of the compression stroke. 2.) use the syncro tool by inserting the syncro vane of the tool. 3.) rotate the tool on the syncro base until the base engages the base notch. The tool should be square and in contact with entire tip of the syncro base. 4.) Install the intermediate shaft so the ring faces the sychronizer. 5.) With no. 1 set at 26 degrees ATDC, install the syncro assembly so that gear engagement occurs when the arrow on your tool is pointing approx. 30 degrees counterclockwise from the front face of the engine block. 6.) install the syncro clamp boltand tighten to specifications torque. 7.) remove the tool. CAUTION: IF THE CAMSHAFT SENSOR ELECTRICAL CONNECTOR IS NOT POSITIONED PROPERLY (CONTACTING THE A/C BRACKET OR FROWARD OF THE SUPERCHARGER DRIVE BELT, DO NOT REPOSITION THE CONNECTOR BY ROTATING THE SYNCRONIZER BASE. REPEAT THE INSTALL PROCERURE. GOOD LUCK!!!