Are these valves done for

Engine's, injection, valve's, timing, crank's etc..

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alexanderfoti
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Are these valves done for

Post by alexanderfoti »

Right, had the head off.

A reminder of the compression test values.

No1 - 400PSI
No2 - 360 PSI
No3 - 320 psi

However, as per this video, no1 was the one misfiring constantly. I eliminated the fuel system as a source. Suspecting a pre chamber issue, I removed the head.

https://www.youtube.com/watch?v=nxXERkfoJCw

What do we thing of these valves. This is the first time I have head a head off an engine before so be gentle.

Click the images for full size versions.

Head:
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No 1
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No2:

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No 3 (lots of carbon on this one, makes sense considering the low compression) :
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No1 Inlet valve:
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No 1 Exhaust valve:
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No 2 Inlet valve
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No 2 Exhaust valve:

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No 3 Inlet valve:

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No 3 Exhaust valve (Seat looks recessed to me?:
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Thoughts?
gilburton
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Re: Are these valves done for

Post by gilburton »

Number 3 certainly looks to have an "edge" on it.
It would make sense to get them all recut with new valves anyway.
alexanderfoti
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Re: Are these valves done for

Post by alexanderfoti »

Indeed, they all have a ridge that can be felt with the nail.

Not sure how many hours on this engine.

Doesn't explain my no 1 misfire though... The pre chamber is a completely passive thing, as far as I can tell, they all look the same.
16VGTIDave
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Re: Are these valves done for

Post by 16VGTIDave »

I watched the video and what I saw/heard was the engine began surging when that cylinder was enabled. If that was the strongest cylinder of the 3, that makes sense to me. The strong cylinder fires well and engine speed increases, the governor reduces engine speed, the 2 weak cylinders fire poorly, the governor tries to increase engine speed, the strong cylinder fires well again. Surge, surge, surge... Disable the strong cylinder and the governor makes the remaining 2 cylinders do all the work. That's my theory...

A good cleaning and, at a minimum, hand lapping the valves would be in order. I'd also be inclined to smooth out the ports as they appear to be very crudely cast. That might increase the power by 1/10 of a horse! ;)
alexanderfoti
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Re: Are these valves done for

Post by alexanderfoti »

The 2 cylinders that are running on that engine are doing so properly. When I enable no 3 cylinder, no 3 cylinder fires erratically on and off (It cant bee seen in the video, but random puffs of white smoke come out of the exhaust when no 3 is enabled). Its because of the erratic firing of no 3 that its all over the place.

With no 3 disabled, I get no white smoke. There is also a noticeable amount of diesel knock coming from no 3. You can hear it when I enable no 3 again in the middle, but its much louder in person.

Very odd. It could be that the no 3 output of the fuel pump is duff, as I have no way of testing that output on another cylinder. Would be surprised as its a completely refurbished pump.

Its probably worth getting the head skimmed as well, save me cleaning all the carbon off.
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coachgeo
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Re: Are these valves done for

Post by coachgeo »

I suspect an injector. Take in head to a place knowledgeable in Bota's. have injectors rebuilt of if it fits the funds get a set from Elsbett. They are designed to handle WVO. Expensive but you'll have proper equipment for the task asked of it. Also once running and IP timed well to match diesel fuel. Then retime the IP to match your blended fuel. No fuel is going to combust properly thus, leave deposits if the time when it is injected at does not match the burn characteristics of the fuel in use.

Suggestion.... stick with one blend. No variations. Time your engine's IP to it. Occasionally do some form of water inject or a mist to clean deposits out.
alexanderfoti
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Re: Are these valves done for

Post by alexanderfoti »

coachgeo wrote:I suspect an injector. Take in head to a place knowledgeable in Bota's. have injectors rebuilt of if it fits the funds get a set from Elsbett. They are designed to handle WVO. Expensive but you'll have proper equipment for the task asked of it. Also once running and IP timed well to match diesel fuel. Then re-time the IP to match your blended fuel. No fuel is going to combust properly thus, leave deposits if the time when it is injected at does not match the burn characteristics of the fuel in use.

Suggestion.... stick with one blend. No variations. Time your engine's IP to it. Occasionally do some form of water inject or a mist to clean deposits out.
Sorry mentioned in the other post but not this.

I personally rebuild all 3 injectors with monarch nozzles, well known for running wvo well. All pop tested at exactly the same pressure.

Moving the injector does not change the cylinder that is misfiring.

IP has been advanced 4.5 degrees for WVO. Have had one blend, the other blends where becuase the tank was not empty of diesel.

I have been using 95wvo/5RUG the whole time i'm running on veg. Either that or 100% diesel.
gilburton
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Re: Are these valves done for

Post by gilburton »

alexanderfoti
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Re: Are these valves done for

Post by alexanderfoti »

Many thanks

Had a chat with Tim today.

The issues with the head, combined with the fact that there is a quite a lot of blow by on this engine, makes me think the bottom end is worn out.

Tim did the valves and the head before I bought it from him, so the damage to the above has happened within 3000 miles. 2850 of those miles where on 100% diesel.

My thinking is the poor compression is causing excess carbon buildup in the valves. As the age etc of the engine is unknown, its cheaper to find a used engine in good condition.
klondikekid
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Re: Are these valves done for

Post by klondikekid »

A quick way to cheaply/not the text book way, to check valve seats is with the head assembled and off the engine is pour a little clean solvent etc. into intake and exhaust ports and if it leaks thru/past the valves, they are not sealing. from the pics some of the valve faces look a little suspect. but yor compression is not nice and even but I would thing passable, rebuilt head should lookalot better than that, was it done properly or just lapped and put back together, a proper valve job incudes valve guides too, check valve lash, if they are not opening enough the cylinder won't breathe, and will be weak.
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