24in of vacuum at idle too high for the 2.8L?


franklin2

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There is a rubber seal that goes around the OD of the thermostat. Do you have that? Does that make it large enough to fit snug in the recess? That picture above looks correct, though a little difficult to read.
 


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SgtDan94

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There is a rubber seal that goes around the OD of the thermostat. Do you have that? Does that make it large enough to fit snug in the recess? That picture above looks correct, though a little difficult to read.
I had to special order the gaskets and O-ring, i should have them tomorrow.

Noob question, can i ask what you are referring to by OD?

The potential problem that i am observing right now is that the the diameter of the thermostat "plate" (the largest part) is wider than the hole that it inserts into. I realize that this is normal, however there is usually a sort of grove that the "plate" of the thermostat sits in to keep it in place. Since, on this engine, the thermostat is installed vertically, and there is no grove, theres nothing to keep is centered while i sandwich everything together. Again, i have not really tried to assemble it yet because i dont have the gaskets, im only observing that this may be an issue, and its almost making me feel like something is wrong.
 
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SgtDan94

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Here you can see exactly what im talking about. This grove does not exist on my Bronco's waterpump.. also, there was no thermostat installed in either the upper or lower. I find it hard to believe this Engine came without a thermostat.

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Perhaps it sat so long without a thermostat that this area built up with gunk/ rust. I will try to chip it out and if i cant, ill probably just get a new water pump
 
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franklin2

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It should have the groove like your picture shows. If you get a new waterpump, that is another couple days wait for it also. I guess we are fortunate to be able to get any parts for this engine at all.

The gasket/o-ring my thermostat had on it looked like the picture below. I am looking for a better picture on the web, but this is all I can find so far. Can you see the black round the plate? It's like a o-ring with a slit in it. The slit fits around the diameter of the thermostat plate. I would think your thermostat would have come with one in the box.

 

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Here's a picture of the gasket. You can barely see the slit in the ID of the o-ring.

 

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Here's a picture of the gasket. You can barely see the slit in the ID of the o-ring.
I see what you're talking about. The thermostat did not come with a gasket or O Ring. Im getting all the gaskets and waterpump tomorrow. I figured i might as well change the pump out now while i have everything drained and disassembled. Im not quite sure why they put the thermostat down low, im sure they had their reasons.
 
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franklin2

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First engine I have ever worked on with it down there like that. And refilling after draining really threw me till I found out how to do it.
 

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@franklin2

does your 2.8 have a tick to it? Do you have any suggestions on how to address it? Also.. what oil are you running? I’m planning to just use 10w-30.. I have now idea what oil is in it now.

I replaced the waterpump and thermostat, was relieved to see the engine run at normal temperature for the first time.
 

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I may have heard a very slight tick, but you can barely hear it with the hood open. It does use some oil. I have to put a quart in it every other full tank of fuel. I get around 300 miles to a tank, so it uses about a quart every 600 or so miles. I use 10w-30 in it.

I believe the 2.8 uses solid lifters. You may need to adjust them. You will have to take the valve covers off, turn the engine over by hand till #1 cylinder is at top dead center firing, and then look up the specs and take feeler gauges and set the clearance between the valve stem and the rocker. Then look at the firing order, turn the engine 1/3 of a turn and set the next cylinder in the firing order.
 

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2.8's are definitely solid lifters. Don't go by 1/3 of a turn, make sure each pair of valves you adjust are with the lifters sitting on the base circle of the cam. You can tell by rotating the engine forward and backward with a breaker bar to make sure neither rocker arm moves.
 

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@19Walt93 @franklin2

I was thinking about adjusting them, I doubt it’s ever been adjusted. My engine has a singular tick that’s pretty loud and seems to get louder after about 30 mins of driving. You know... Just by sticking my head near the engine, I almost want to say it’s not coming from the top of the engine. It almost sounds like its
Coming from down low and center.. hard to explain..

I can definitely hear the lifters working if I put my ear close enough.. they don’t sound out of the ordinary.
 

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If you check the adjustment then you can rule it out. Once you get it making noise in good shape, take a long skinny screw driver and use it as a stethoscope to pinpoint the noise. Or you can actually use a stethoscope if you have one.
 

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@19Walt93 @franklin2 @8thTon

well I made the adjustments today. This is what i found on cylinder 5 upon removing the valve cover..

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They’re corroded, and I’m most certain they’re not getting oil. Ive basically pin pointed the tick/ knock coming from cylinder 5s valves. I even used the screwdriver stethoscope trick while idling, even after I made the adjustments, and all things point to #5.

At cylinder 5, the rocker arms had no space/ play between the valves when they should have. I triple checked to make sure cylinder 1s valve was open... according to the manual, which should have allowed me to adjust cylinder 5s lifters. They were too tight.

Oil travels up through the pushrods right? Does this mean they’re clogged up? Can I replace the rods without doing a complete overhaul? The engine has good compression and plenty of power. It’s just this damn tick.. heck .. at this point I’m going to call it a knock. It’s getting worse.

All other cylinders were basically within spec, I made a few minor adjustments.
 
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franklin2

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I think this system is a little different, and gets it's oil from somewhere else to oil the rocker shaft. I will have to look harder to find something on it. Here is a excerpt from a article in the tech section.

Additionally, oiling problems were common, and added to the poor reputation of the North American 2.9. Many poorly maintained or high mileage engines exhibit serious valve train noise. This problem is due to a number of design faults. Valve train oil pressure was entirely dependent upon a supply fed through the two center cam bearings. Even slight bearing wear could cause complete loss of oil pressure to the hydraulic valve lifters, rocker shaft, and rockers. Excessive internal “bleeding” through the half-moon camshaft thrust plate also contributed to this, though this can be remedied by reinstalling the thrust plate in an upside-down position. This condition is sometimes mistaken for ticking fuel injectors. This condition isn’t a cause for alarm unless it does it very loudly or after long freeway trips. If it does have the oil pressure checked, it could be low.
 

SgtDan94

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I think this system is a little different, and gets it's oil from somewhere else to oil the rocker shaft. I will have to look harder to find something on it. Here is a excerpt from a article in the tech section.

Additionally, oiling problems were common, and added to the poor reputation of the North American 2.9. Many poorly maintained or high mileage engines exhibit serious valve train noise. This problem is due to a number of design faults. Valve train oil pressure was entirely dependent upon a supply fed through the two center cam bearings. Even slight bearing wear could cause complete loss of oil pressure to the hydraulic valve lifters, rocker shaft, and rockers. Excessive internal “bleeding” through the half-moon camshaft thrust plate also contributed to this, though this can be remedied by reinstalling the thrust plate in an upside-down position. This condition is sometimes mistaken for ticking fuel injectors. This condition isn’t a cause for alarm unless it does it very loudly or after long freeway trips. If it does have the oil pressure checked, it could be low.
I wonder if that also applies to the 2.8
 


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