Rebuilt engine is a dog out of the hole

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

I've would have never guessed a motorcraft rotor under a Chevy cap.

Me either, that's why it's under a Ford cap . It's on a Ford engine too )))

 

[a70eliminator]

Re: Rebuilt engine is a dog out of the hole

Oh crap i got lost in another thread about a 5.7 SSSshhhhhissh

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

These things are not easy to track down at times ---- one thing at a time.

"Things on the blink" ---- please, double check you charging voltage and battery connections.


OFM

Charging is fine. Voltage is fine. Went to the batts with a meter and verified both running and not.

I suspect I have a single ground up under the dash that needs some care. I just have not found it. These items are all on a house circuit though. I completely rewired everything on this boat myself a few seasons ago, so I know they are separated. The only thing on my starting circuit are the engine, the trim and one bilge pump

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

Oh crap i got lost in another thread about a 5.7 SSSshhhhhissh

LOL.. it's OK.. I needed the smile!

 

[Apollo75]

Re: Rebuilt engine is a dog out of the hole

It is wrong for me to jump in with both feet -- it is your boat and you know her better than me.

You initially stated you were breaking in something --- long block, short block, complete engine ?

Else, I missed something.

OFM

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

Call it a long block.. Original cam and crank though.

New pistons, rings, pushrods, rebuilt heads. Cyl walls refinished but not bored. This engine was redone not too long ago from the looks of it the mechanic said. Most everything was in very good shape except the pistons and rings from the water intrusion

 

[Apollo75]

Re: Rebuilt engine is a dog out of the hole

Call it a long block.. Original cam and crank though.

New pistons, rings, pushrods, rebuilt heads. Cyl walls refinished but not bored. This engine was redone not too long ago from the looks of it the mechanic said. Most everything was in very good shape except the pistons and rings from the water intrusion

Okay, if you are sure the pistons are the same compression ratio, deck height is the same and head gasket is not like .030" thicker, etc., All of this can effect power.

Added : Sorry, your heads rebuilt, or new re-builts with different sized combustion chambers ?

Give me a sign.

OFM

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

Okay, if you are sure the pistons are the same compression ratio, deck height is the same and head gasket is not like .030" thicker, etc., All of this can effect power.

Added : Sorry, your heads rebuilt, or new re-builts with different sized combustion chambers ?

Give me a sign.

OFM

Originals heads were rebuilt. As for the rest I can't say. The guy who did it builds High perf engines. I presume he got those parts right. He did not need to machine any surfaces. That was one of his comments. He said that engine had been rebuilt not long ago (I've had it for 4 years - not many hours) and was in very good shape overall.

 

[Apollo75]

Re: Rebuilt engine is a dog out of the hole

There may be a problem --- I would get the distributor figured out and go to the Prop forum and ask hwsiii to figure you out a new prop.

From what you state the engine runs too good to be much wrong with it.

I think you did well.

OFM

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

Yeah, I am gonna dig into this distributor problem..

As for the prop, I run a SX-DP. I am already running a D-5 set which is pretty light. I have a D-6 set which I could turn before but I liked lower end responsiveness of the D-5 set in rough seas.

I was actually thinking after the rebuild I would be able to move up to the D-6 and get some top end back. What I am saying is I should be able to scream out of the hole with the prop set I am presently running..

 

[79SRV195]

Re: Rebuilt engine is a dog out of the hole

HI, I am new here and not sure if you problem has been fixed or not. I have had a lot ford small blocks in mustangs and capri's. If the motor has been rebuilt prior to you owning it the camshaft may have been replaced. Ford uses two different firing orders in the 302. I cant remember what they are. 4 of the cylinders are the same and the other 4 are different. the engine will run perfectly smooth if incorrect just lack power. I would try the other firing order and see if it helps. Hope this helps.

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

Hey 79,

Thanks for chiming in. You have brought up an interesting point. I DID know there were two firing orders for the 302. The Volvo manuals all show the 137... order which is how I set it back up.

BUT the re-builder brought up a puzzling point about the cam in the engine. As I mentioned it was bored 30 over already, so it's clear there was a rebuild done at some point, presumably not long ago. We reused the old cam since it was in great shape, but this "old" cam may be a "new" cam from a previous rebuild. He said it was odd not to see a roller cam in the block since the lifters were roller cam style.

Based on that info it's entirely possible that I have the OTHER cam I suppose. I DID replace wires a couple seasons ago and of course I just replaced them one at a time using the same order that was setup..

I wonder....

-M

 

[Knightgang]

Re: Rebuilt engine is a dog out of the hole

Put them in the other order and check it out. Gotta be somehting that simple. Otherwise, you could be looking at a fuel issue, but chase this dog first...

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

So I finally got back to working on the boat today..

I got to play with my new advance timing light. Cool toy. I checked the base timing per the manual but removing the SPOUT (puts the computer in base timing mode). The advance gun says my base timing is at 6 deg BTDC. It's supposed to be 5. Close enough in my book.

Then I checked the advance with the gun. No advance in base timing mode. I think that is correct. Put the SPOUT back in and ran it up to 2500.

Here are my numbers
2500 = 20 deg
3000 = 22 deg
3500 = 25 deg

Is it supposed to fall off like that?

For those who are going to ask the distributor uses a Hall Effect module. Not centrifugal or vacuum.

I have another distributor I can throw in to try if this seems wrong, but that one was the one I started with when I complained about the low power in the first place. It has not been load tested with the present distributor, but the advance was not checked with the other one. Long story about why I have swapped them, but the problem existed with the other one.

-M

 

[a70eliminator]

Re: Rebuilt engine is a dog out of the hole

Yes it looks good, as RPM's increase the spark happens earlier, 25 degrees BTC plus the initial 6 degreees and you have a total advance of 31 degrees BTC. The total timing advance spec on my 1990 5.8 is 30 degrees. I don't think ignition timing is your problem.

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

OK.. Now that it is timed correctly I am gong to throw a new cap and rotor in it to deal with the carbon problem and see how it runs.

Based on what I see I think I suspect I know what the problem could be. tell me if I am off base. When I timed it initially for a water test I couldn't find the timing scale on the balancer. BUT when I threw the light on it the timing mark was pretty much aligned with this big groove in the balancer, so I set it to the thinking the groove must represent either 0 or 5 deg. Yes odd, but that was all I had.. I ran the first 2 hours like that.

I later found the scale and timed it to that correctly, base timing more the whole works. I ran it another 4-6 hours. After that, since it was still a dog, I pulled the cap. That is when I found everything coated in black carbon and the electrodes under the cap as well as the rotor tip were all arced to hell.

That groove, if I estimate correctly, is like 60 or more degress BTDC. My guess is there was a ton of arcing under the cap under the first two hours of break in. After that After that I think the cap and rotor were just junk even though I had it timed right for my second run.

Would that explain low end power loss? Again she runs great up on plane, just has no get up and go.

Oh yeah, one more thing. When I was checking the advance I noticed what appeared to be a "skip" with the strobe as the rpms increased. Is that normal or could it be something?

I have not tried the alternate firing order order yet. I was shooting the bs with the guy at my local parts store and mentioned trying the other order. he said a cam change would not change the firing order, just the timing. BUT he is not a Ford guy.. Looking at the order they are:

13726548 (this is spec according to Volvo Penta)
15426378 - Many 302's seems to have this order when you google.

The difference seems to be cyl pairs 54 and 37 are swapped. Seems plausible to me this could be my problem sine I have had wires mixed up once or twice in the driveway and it runs fine. I AM sure it's set properly to 13726548 right now though. Since my cam seems like it may have been changed would this indeed be a possible issue?

Thanks. A lot of in and a lot of questions in here. I appreciate the feedback

 

["G"]

Re: Rebuilt engine is a dog out of the hole

Do yourself a favor and check that your distributor (if it is spring actuated) has good springs (not broken) and the idle is low enough so that the centrifugal force on the springs are not beginning to advance. If you get your engine idle down to 600 you should be OK. THEN check and adjust timing. Rev the engine while you have the light attached to see if you are getting advancement too.

The vibration dampener on my Chev 350 4 bolt was found defective (it had slipped around). My buddy tells me that was a common thing with chevs. Never heard of it on Fords.

You can check TDC with a stick (best with a dial indicator). Make sure the valves are right/not too tight and that will sort of assure the timing gears were set up right.

One more thing.... set up your vacuum gage and see what vacuum you have. Maybe there is a lack of vacuum or leak issue?

Good luck.

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

Hey G.

As I mentioned this is not a centrifugal advance system. Completely governed by computer. Look up Hall Effect ignition and TFI-IV.

I did the stick in the cylinder today to verify TDC before I put the dist back on. I know all is well there.

As for the balancer, I have heard of it that, but I know it's not a common occurrence in general. Since there was no problem prior to the rebuild regarding timing I am ruling out that being a problem right now. Plus once I did TDC and put the light on it today the marks all lined up, so I think the balancer is go. I was at 0 deg on the scale at first crack..

I am still thinking that with the timing being so far out for the first few hours and trashing the cap and rotor that my problem may be very simple. Can someone let me know if that is a possibility?


M

 

[bruceb58]

Re: Rebuilt engine is a dog out of the hole

Timing being out will have no effect on your cap.

Just to correct a previous poster, your total advance is not 31 degress. It is what you measured which is 25.

 

[mcleaves]

Re: Rebuilt engine is a dog out of the hole

Timing being out will have no effect on your cap.

Just to correct a previous poster, your total advance is not 31 degress. It is what you measured which is 25.

Hey Bruce,

I don't want to sound dumb but isn't there a larger distance from the rotor to the cap electrode at the time of spark whe you turn the cap?

If not maybe you could shed some light on why the electrodes and rotor tip were all arced to hell. I ahve to belvei this factors in here some place.

Also, thanks for clarifying my advance. Problem is I have no idea if that is the correct advance. I am pretty surprised the VP shop manual only says to check it and make sure it advances, but doesn't say how much and and what RPM's. Actually the timing gun manual gave better info on what RPMS to run up to, but still no numbers on advance.

M