Rebuilt engine is a dog out of the hole

[mcleaves]

Hey guys. I am about 8 hours into my break in period. Thanks for the advice on that.

But here is my present issue. During this time I have been trying to get her timed right. I have a horrible time getting up on plane. Once I am up She runs great. I have been making some long runs so I am not dealing with pulling tubes and such, but it WILL be a problem if I don't sort it out.

Here is what I have done so far. All timing has been done using the shop manual procedure of removing the spout connector to set the base timing.

1. Initially I thoguht the deep groove on the balancer was the mark for 5 BDTC. I set the timing to that. Took forever to get out for the hole. I decided to that maybe the mark was zero and moved it to what "I" thoguht would be about 5 deg before that. Ran worse. I moved to about 5 deg on the other side. Ran better. Moved it a little more. Ran a little better, but not like it used to out of the hole. Called it a day on the water
2. Next day I go out to tackle it. Clearly that mark was NOT a timing mark. After some REALLY hard looking I find the marks on the balancer. Yay! Looking at the balancer from the front of the engine, the marks on the right are BTDC and the ones on the left are ATDC. At least that is how it is marked. I send the wife down with some white nail polish to mark 10 before, 10 after and 0 (I'm 6.5" - I could look but I couldn't touch ) I check the timing and it looks like I was only off by 5 deg. I moved it to 5 deg BTDC, which is to the RIGHT of the 0 mark. Next time out on the water It's really no better.
3. Now I decide to check it again. This time I try to see if there is any advance. I didn't have the manual with me, so at first to try to check the advance with the spout out. No advance. Put the spout back in and it advances well, EXCEPT it advances in the opposite direct of what I expected.

If this were the picture of the timing marks

ATC--------------BTC
10--5--0--5--10

The advance ends up out here

ATC---------------BTC
10--5--0--5--10---------ADV

I would have expected the advance to be AFTER 0.

Clearly something is wrong, or I don't understand what should be happening. Can a balancer be installed backwards? The balancer was NOT replaced in the rebuild.

Oh yeah, This is an OMC/VP Ford 5.0 EFI

 

[Don S]

Re: Rebuilt engine is a dog out of the hole

It has to be at 5?BTDC, not ATDC.
Did you follow the steps on page 4-2 of the MFI Diag. manual?

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

I have had my head in so many manuals I forget which one I found the steps in!!! But I followed the ones that were in there. From memory they are pretty short. Remove the spout, set base timing to 5 deg BTDC, re-install spout.

In a nutshell at least. Haven't looked at them in a week..

According to my scale up above are you saying I am NOT at 5 deg BTDC? I feel like the way it's advancing I am not.

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

I just marked where I set the timing to in red

 

[bruceb58]

Re: Rebuilt engine is a dog out of the hole

i am cornfused! Are the marks you have posted on th balancer or the timing tab. If its the timing tab, you have it backwards.

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

On the balancer, standing in front of the engine looking down. On a Ford, the marks are on the balancer and the needle is on the block .

I know, not what I expected to find either!

While this is not MY engine, this is another 302, from the same perspective

http://image.customclassictrucks.co...100_ignition_system+302_harmonic_balancer.jpg

 

[Maclin]

Re: Rebuilt engine is a dog out of the hole

I would have expected the advance to be AFTER 0.

After 0 is retarded. Before 0 is advanced. Mechanical advance advances more so it moves in the direction you see.

Per Bruce's comment, since the marks are on the balancer your initial advance setting is corrrect and the direction of the mechanical advance is correct.

What the heck is a spout.

 

[bruceb58]

Re: Rebuilt engine is a dog out of the hole

That looks correct then. So when you increase the RPMs the index mark on the block relative to the balancer isn't going to the right?

 

[Apollo75]

Re: Rebuilt engine is a dog out of the hole

Hey guys. I am about 8 hours into my break in period. Thanks for the advice on that.

Put the spout back in and it advances well, EXCEPT it advances in the opposite direct of what I expected.
[/LIST]

If this were the picture of the timing marks

ATC--------------BTC
10--5--0--5--10

The advance ends up out here

ATC---------------BTC
10--5--0--5--10---------ADV

I would have expected the advance to be AFTER 0.

Clearly something is wrong, or I don't understand what should be happening. Can a balancer be installed backwards? The balancer was NOT replaced in the rebuild.

Oh yeah, This is an OMC/VP Ford 5.0 EFI

Your advance is correct --- should be BTDC not ATDC.

Before--Top--Dead--Center ---- before the piston arrives at top dead center.

OFM

 

[bruceb58]

Re: Rebuilt engine is a dog out of the hole

ATC--------------BTC
10--5--0--5--10

The advance ends up out here

ATC---------------BTC
10--5--0--5--10---------ADV

I would have expected the advance to be AFTER 0.

Advance makes the spark happen earlier hence more BEFORE TDC. You should use an advance timing light to determine what the maximum advance is. What distributor do you have? Are you setting the advance with the distributor in base timing mode?

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

The mark IS going to the right. I guess it's setup correctly then. In my head I had equated advance to ATDC, so I expected it to go the other way. SO it sounds like I am timed correctly then, or at least close to it. Hmm

The spout disables the computer so you are not fighting it while trying to set the base timing. Other systems call it other things I guess. Ford calls it a spout.

So, if the timing is good where is my low end power going?

No stumble runs smooth as hell. All new filters..

Can the throttle body be an issue? I didn't remove the TPS (throttle position sensor), but I did take it off the intake plenum and replace the gaskets

M

 

[haulnazz15]

Re: Rebuilt engine is a dog out of the hole

I'd get a wooden dowel and turn the engine by hand until you have the engine at TDC, then check to see what it is showing on the balancer. At least that would give you a starting point. Shouldn't base be a 8 BTDC?

 

[bruceb58]

Re: Rebuilt engine is a dog out of the hole

Maybe you should measure compression and see how things are doing there. Maybe rings aren't right or a valve has a problem. Its an easy test and will at least get that variable out of the equation.

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

Advance makes the spark happen earlier hence more BEFORE TDC. You should use an advance timing light to determine what the maximum advance is. What distributor do you have? Are you setting the advance with the distributor in base timing mode?

Thanks! Now I get it. Not sure why I thoguht the opposite. I have an inductive timing light. Is the advance light something different? Plus the advance seems to moving off the scale pretty quick, so i don't know how to tell how far it is..

I forget the name of the dist, but it uses the Hall Effect mechanism

Yes I am removing the plug to get into base timing mode. There is NO advance happening in that mode though, just once the computer is engaged

 

[bruceb58]

Re: Rebuilt engine is a dog out of the hole

With an advance timing light there is a little dial on t e back of it. basically, you rotate the dial until the mark on the engine meets the TDC mark on the balancer and then you can read what the timing is off of the light. You can measure timing out to 30+ degrees that way.

It sounds like that is ok though. Would be nice to see what your total advance is but I don't think that is your problem unless you were having issues before your rebuild.

 

[bruceb58]

Re: Rebuilt engine is a dog out of the hole

http://www.amazon.com/Equus-3555-Ad..._1?ie=UTF8&s=automotive&qid=1254510517&sr=8-1

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

With an advance timing light there is a little dial on t e back of it. basically, you rotate the dial until the mark on the engine meets the TDC mark on the balancer and then you can read what the timing is off of the light. You can measure timing out to 30+ degrees that way.

It sounds like that is ok though. Would be nice to see what your total advance is but I don't think that is your problem unless you were having issues before your rebuild.

I'll grab that light and give it a check. But I think I agree that it's doing the right thing now. I just thoguht I was reading the scale wrong..

I had no issues before the rebuild. I had some water intrusion back in the spring for a bad riser. Engine great up until that point.

The rebuild was a simple one. Orig cam, orig crank. New pistons and pins, pushrods, rehoned, rebuilt heads. New oil pump

 

[bruceb58]

Re: Rebuilt engine is a dog out of the hole

I would still do a compression check to see how the break in is going.

Good luck!

 

[EddiePetty]

Re: Rebuilt engine is a dog out of the hole

I'd get a wooden dowel and turn the engine by hand until you have the engine at TDC, then check to see what it is showing on the balancer.

.....I'm NOT a Ford guy but to establish a bench mark I would do as Haulnass15 suggest. In my experiences I have seen quite a few harmonic balancers slip in the hub resultant in erroneous timing indications.

FWIW...Ed in 'ol Virginny

 

[a70eliminator]

Re: Rebuilt engine is a dog out of the hole

I've never seen any Ford v8 run 5*BTC, most all fords run 6-10 degrees BTC. Your problem may lie somewhere else. Double check and triple check your firing order, that one will get you every time.