Ignition Timing

[kwoolard]

I have been battling an overheating problem the entire summer. Check out the discussion: Engine Overheating <br /><br />I have tried everything except play with the timing. I have been reading up a little on that topic and have a few questions. First of all, without even checking the timing, I have no reason to believe that my engine is too far advanced. The engine doesn't knock under load. With my particular engine the cooling raw water is circulated through the exhaust manifold and back to the engine to help it get up to operating temperature quickly. However, my temperature keeps climbing passed the operating temperature. Therefore, I am leaning towards a retarded ignition timing. Meaning my exhaust manifolds are getting too hot because there is combustion during the exhaust stroke. A couple more reasons why I believe it is too retarded: when I remove the water line coming from the exhaust manifold back to the T-Stat housing the temperature drops dramatically, and another reason: the paint on my exhaust manifolds (right at the exhaust ports) turned from Ford blue to chalky white material two days of running after painting. <br /><br />My question is, how many degrees of retarding will cause the engine to run 30-40 degrees F over the proper temperature? Also, based on my observations, does this look like a retarded igntion timing problem?

 

[Bt Doctur]

Re: Ignition Timing

What kind of engine? year,make.<br /> unless a true fireproof paint is used ,it will blister from the heat right at the port.raw water systems usually circ. out the risers until the therm opens not thru the manifolds.

 

[Don S]

Re: Ignition Timing

I didn't read much of you previous post. Did you check the advance timing? <br />Set the timing to the book idle setting (somewhere around 10º BTDC) then check it at 3000 rpm, what is the timing at then. I am guessing, as I don't have any Ford specs handy, but would guess around 25º to 30º BTDC at 3000rpm.<br />Also, what is your wide open throttle rpm.

 

[Boatist]

Re: Ignition Timing

Kwoolard<br />Without knowing your engine type can not say for sure but I dout it is retarded timing. If it were retarded so far as to over heat it would run very bad. <br />My gut feeling right now says you have a plugged up exhaust manifold or riser. This is a very common problem when running in salt water.<br /><br />Does it cool down when you slow to a idle and heat up at higher RPMS???

 

[cc lancer]

Re: Ignition Timing

On your 74 302 Ford, 10 degrees on the timing, and a spread of 26 to 31 on the dwell. I would rather see it around 30. If the engine knocked back off 2 degrees.<br />But<br />You said it cranks good, no knock under load, but is a little slow trying to get top RPM.<br />Please explain this to me:<br /><br />The motor is equipped with an un-orginal belt driven water pump. While cruising with the belt driven water pump supplying the water the engine runs about 180-190, which I feel is too hot. I have been told that for raw water cooled engines the temp should be around 165 max. I have a new 140 degree thermostat installed. Well, just out of curiosity, I decided to remove the belt driven water pump and use the sterndrive pump which is orginally the way it was set up. Ran the motor this past weekend and as soon as I got on plane the engine shot up to boiling point (212) !!!!<br /><br />Was this un-original pump you removed mounted just to the right of the engine water pump?

 

[kwoolard]

Re: Ignition Timing

CC, no the un-original water pump is on the left side of the circulating pump.<br /><br />Boatist, the engine will heat up to 165 degrees on the muffs with a 140 degree thermostat after about 10 min.<br /><br />While running it at full throttle it will hold at the high temperature and I will have to put the drive in neutral and rev it up to cool the engine down to about 180.

 

[Bt Doctur]

Re: Ignition Timing

Beginning to sound like more of a restriction in the cooling system or its getting exaust bubbles in the system.If the conversion was done properly the impeller would have been removed from the drive.More reason to suspect exaust bubbles entering around the water pump body or base.

 

[Don S]

Re: Ignition Timing

Without a manual, this is a real PITA to troubleshoot. Did find a parts book though and now I have a couple of questions.<br />Below is a picture of where the hoses should be hooked up. Could you verify the hoses are in the correct place? Especially the ones going to the elbow.<br /><br />Also, since you did mention in a previous post that you had different manifolds and risers, do you have block off plates between the risers and the manifolds? They need to be there to prevent water flow between the manifolds and risers.<br /><br />Here is the picture, kind of crude, but hope it works.<br /><br />

 

[cc lancer]

Re: Ignition Timing

Look at Dons drawing, did you remove the raw water pump from the engine.<br />The reason I ask I have a boat that may be coming in for restoration, 1977 Glastron, with a Ford 302 and it has a raw water pump, and I thought it was mounted on the right side when you are facing the engine.

 

[Hog Wild]

Re: Ignition Timing

I just want to 2nd the above thoughts. This is certainly a water flow issue, nothing more. Don't over think this problem. You are either getting wrong water, not enough water, not the right water flow. Anything else and the engine wouldn't run so nice and have other symptoms.

 

[kwoolard]

Re: Ignition Timing

Thanks for your responses! I have a Seloc manual, however it shows the water supply coming from the outdrive. Does the picutre above also have the impeller in the outdrive installed? Also, is the raw water pump in the diagram pulling water through the outdrive or from a seacock? My water lines are plumbed as described above. If you read my previous thread you see that I have disconnected all the water lines one at a time to check the water flow, all seem to have good flow...steady stream. Like I said, if I disconnect the water coming from the front/high position on the exhaust manifold(this line feeds the thermostat housing) my temperature decreases dramatically. Therefore, I feel the recirculated water is not leaving the engine.<br /><br />Bt Doctur, if I removed the outdrive impeller I would have to put my belt driven raw water pump back in line. By doing so the upper gearcase would not get the cooling it needs. I have posted that question in the past, and everyone stated that my particular drive needed cooling water. What kind of volume should I be getting from the outdrive pump? Would a clear hose between the T-Stat housing and the riser tell me whether I am getting exhaust gases in the water or tell whether I am getting the proper volume of water to the engine?<br /><br />From what you guys are saying, my outdrive impeller (just replaced a few months ago) is not supplying enough water to the engine. Therefore, I may just put the raw water belt driven pump back on. The only problem I have is that I have with this pump is that when mounted there is no way to adjust the tension on the belt other than by wedging the split pulley together. Does anyone know of an alternator type mount for these Jabsco raw water pumps?

 

[kwoolard]

Re: Ignition Timing

One more thing Don S, I have the Osco center rise manifolds with 3" elbows. And I do have a block off plate between the elbow and the manifold.

 

[Don S]

Re: Ignition Timing

The drive impeller should have no problems suppling enough water for your raw water cooled engine. Some things you should look at though, would be the tube from the water pump to the upper gear case, the connector for that tube in the upper gear case, the connection between the drive and the pivot housing (Oring and gasket must seal) the hose from the pivot housing to the transom shield, even the tube that goes through the transom shield could be plugged with something.<br />The raw water pump housing may be bad, gaskets not sealing, or the seal on top of the pump housing could be missing or bad.<br />How about the pump base in the lower gear unit. Was it changed. It could have the wrong one installed and is bypassing a lot of your water.<br />They look the same, but are not.<br />The fact that the temp goes up immediatly tells me you are getting air into your water pump. While on plane, the pump is out of the water and will suck air instead of water.

 

[cc lancer]

Re: Ignition Timing

Well, just out of curiosity, I decided to remove the belt driven water pump and use the sterndrive pump which is originally the way it was set up.<br /><br />In your cooling configuration the raw water pump must be in there for your particular cooling system. The best I can remember this was used as a circulating pump and is unique for that engine in that time period.<br />I looked at the Seloc manual and did not see your cooling configuration in the manual.<br />Call Wooten in Rocky Mt., NC they may have the correct brackets and pulleys for your engine.

 

[kwoolard]

Re: Ignition Timing

CC Lancer, according to my Seloc manual the 888 used the outdrive water pump and the engine's circulating pump. The configuration I am referring to is the 888 - raw water cooled - log style. The only difference in mine is that I now have the center rise type manifolds. The plumbing is the exact same. There was no other "recirculating pump" shown in the plumbing diagram. Also, this raw water pump that was installed was not originally equipped. The previous owner put in on to just to get more water flow. However the way he had it plumbed was the outdrive pump was pumping to the belt driven pump. So if he had a failure in the outdrive pump he was screwed and wouldn't get the water flow. That is why I went back to the orginal setup. <br /><br />Thanks CC Lancer for the contact!

 

[Don S]

Re: Ignition Timing

CC<br />The circulation pump is item #31 in the drawing below. This is what is called the water pump in automotive applications. The raw water pump on the 888 was in the drive the same as in all engines using the R, MR, and Alpha drives. Including the MC1, 165, 470 and other Alpha styles. <br />I had an old GlasPly that was converted from the 302 to a 351 and had a closed cooling system with fresh water cooled manifolds even and the raw water pump in the drive even worked for that. So the need for a belt driven pump is just not there.<br />But finding the reason for the low water flow is.<br />I have found kinked hoses, hoses with bubbles on the inside that almost closed off the complete hose, you name it.<br /><br />

 

[cc lancer]

Re: Ignition Timing

Hey Don:<br />Just as I hit the reply button a Tornado was going through the area, lost electricity and that was all.<br />Called the customer back and mounted to the right of the circulation pump is a factory mounted<br />water pump. He said there was a big hose from the bottom of the thermostat housing, to the pump then a hose going back to the outdrive.<br />But the outdrive is a Volvo, my mistake.