I lost one of the cylinders on my Acty today when driving. Lost of power and confirmed I am now running on only 2 of the 3 after a compression test with the fist two being around 175 psi and the third dropping down to around 22 psi. Will have to pull the head and rebuild or replace so starting the ordering of parts now. The question I have before I attempt anything else is weather or not I will be able to do the work with the engine in or if it really is worth pulling it out first? I am open for any hints, tips, recommendations, advice, etc. Love this little truck so going to fix it what ever the case just want to make it as easy as possible. Thanks in advance! - Jon.
How sudden was this lost of compression? I would start by looking inside the cylinder to see if it a bent valve, or a hole in piston, or?? you might be able to do this with engine in. I wouldn't , not knowing how far down the rabbit hole your going. okay it's not a hole in the piston, you have a little compression so maybe head gasket?
Going to run my boar scope/camera down it tomorrow but ran out of light before I got that far tonight. The good news is it didn't make any big noise and doesn't seem to have lost any coolant so my current guess is a hole in the piston, or burnt valve but it could be a head gasket as it stayed running fine other than low power so at least I didn't loose the timing belt (was done recently). Just don't want to fight the job by trying to do it in the car if pulling the engine is the best way even if it is only a burnt valve. However at this point the head is likely to come off whatever the final issue is so not sure running a scope down it real is going to provide me a lot more information that would change much in the end. Thanks.
Found a video of someone putting a head back on, what looks like an HA4 Acty, with the engine still in the truck. So it looks like at the very least I can scope the truck tomorrow and if it looks like its just a valve/head issue I can pull the head with it in the truck still and go more into it if I see anything suspicious in the cylinders or with the pistons.
Well, put the scope down it and can see where the valves hit the piston, hard to see everything but looks like it was the edge of two vales. I am not going to know for sure how bad tell I pull the head but based on what I can see I think everything is in good enough shape I am going to see if I can manage with this engine by pulling it and rebuilding, or replacing, the head without pulling the engine. I might regret this choice in the end, however considering I use the Acty more than any over vehicle we own I am hoping I can get it back onto the road quick this way. Then I am considering picking up a spare engine to rebuild for when this one ends up giving up completely.
I pulled the head without removing the engine. It’s actually a pretty quick job- you may need to lower the engine off of the engine mount by the timing belt to get enough room to pull it out. did you do the job yet?
Thanks for the information. I just got the last of the parts I needed to do the job this week and planning to do the work next weekend if the weather is decent (heavy ran and hale today and maybe tomorrow). Also going to swap in new engine mounts at the same time.
Got the used/new head pulled apart valves seals replaced and re-lapped the vales as well as set the clearances. Got part of the way into pulling the head and based on the current state I think I have a chance of having it done tomorrow or maybe by Monday evening depending. Have a few other minor issues I am finding that I am going to see if I can sort out as well if not will order parts and may have a little more time before I can drive the truck again. We will see.
Well turned out that I must have had some kind of strange reflection from the back of the valves or something when I put the camera in. After pulling the head it was a burnt valve.
