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Sorry in advance, this is going to be long.
My recently completed 91 intercooled 12 valve engine seems like it's down on power. There is also a lot of white smoke out the exhaust both at idle and on the throttle.
A little background on the engine:
Originally out of a 98 2nd gen, this motor received one replacement piston on cylinder 5, all cylinders were honed and re-ringed, cylinder head was resurfaced and got a valve job, new head gasket and all new injectors from DAP.
I've driven the truck about a dozen times since installing the engine, not very far but each trip between 1 & 3 miles. Seems to be lacking a lot of power.
The engine starts extremely easily whether it's ice cold or fully warmed up. I would venture to say it does not even crank over a full revolution before it fires up and idles quite smoothly. When applying throttle however it feels like there is a stumble or a misfire.
Assuming a misfire was the cause of the sluggishness, I proceeded to try to pinpoint which cylinder or cylinders was not contributing by using a laser thermometer on the exhaust manifold ports after the engine had been running for about 5 minutes.
I will try to attach a video of that experiment in response to this post, but for now the temperature readings I got on the cylinders are as follows:
#1 127 deg
#2. 140 deg
#3. 128 deg
#4. 136 deg
#5. 163 deg
#6. 151 deg
It seems as though number one and number three cylinders are running the coldest.
Just for my own curiosity, and not that I don't trust the quality of diesel auto power injectors, but I swapped injectors number one and number five and then repeated the test. The temperatures stayed the same indicating that the injectors are not the issue.
Do you guys think the temperature variances are enough to indicate the issue or am I jumping the gun here?
The only other thing that has me concerned, is that my original 91 engine was also misfiring on cylinders one and three when I bought the truck. Granted when I tore that engine down cylinder number one was completely wiped out and cylinder 3 was scored.
But I can't help but Wonder if the ve injection pump which was transferred over from my original engine to this 98 engine, could be causing my issue. I've researched how the pump comes apart and it seems that there are six "cam lobes" for lack of a better term that fire the corresponding six cylinders. Could one or more of those lobes be worn down in my pump?
Is there a way to see those cam lobes without completely removing the injection pump? In other words could I take the top metering half of the pump off and be able to view that cam plate?
Thanks in advance for any help.
My recently completed 91 intercooled 12 valve engine seems like it's down on power. There is also a lot of white smoke out the exhaust both at idle and on the throttle.
A little background on the engine:
Originally out of a 98 2nd gen, this motor received one replacement piston on cylinder 5, all cylinders were honed and re-ringed, cylinder head was resurfaced and got a valve job, new head gasket and all new injectors from DAP.
I've driven the truck about a dozen times since installing the engine, not very far but each trip between 1 & 3 miles. Seems to be lacking a lot of power.
The engine starts extremely easily whether it's ice cold or fully warmed up. I would venture to say it does not even crank over a full revolution before it fires up and idles quite smoothly. When applying throttle however it feels like there is a stumble or a misfire.
Assuming a misfire was the cause of the sluggishness, I proceeded to try to pinpoint which cylinder or cylinders was not contributing by using a laser thermometer on the exhaust manifold ports after the engine had been running for about 5 minutes.
I will try to attach a video of that experiment in response to this post, but for now the temperature readings I got on the cylinders are as follows:
#1 127 deg
#2. 140 deg
#3. 128 deg
#4. 136 deg
#5. 163 deg
#6. 151 deg
It seems as though number one and number three cylinders are running the coldest.
Just for my own curiosity, and not that I don't trust the quality of diesel auto power injectors, but I swapped injectors number one and number five and then repeated the test. The temperatures stayed the same indicating that the injectors are not the issue.
Do you guys think the temperature variances are enough to indicate the issue or am I jumping the gun here?
The only other thing that has me concerned, is that my original 91 engine was also misfiring on cylinders one and three when I bought the truck. Granted when I tore that engine down cylinder number one was completely wiped out and cylinder 3 was scored.
But I can't help but Wonder if the ve injection pump which was transferred over from my original engine to this 98 engine, could be causing my issue. I've researched how the pump comes apart and it seems that there are six "cam lobes" for lack of a better term that fire the corresponding six cylinders. Could one or more of those lobes be worn down in my pump?
Is there a way to see those cam lobes without completely removing the injection pump? In other words could I take the top metering half of the pump off and be able to view that cam plate?
Thanks in advance for any help.
