Haven't been on the forum in quite a while - real life getting in the way of forum life! But I'm needing some pointers as to what's wrong with my bus. Its a '75 1600 running standard vacuum dizzy, solex carb etc. The engine is a recon engine which is about 6 years old and has done about 20K in that time with regular servicing. I was driving home this evening and it seemed to be a bit down on power. It had been perfectly fine on the drive to work in the morning. A mile or so from home a steep hill almost stopped me. There was no nasty noises, no red light/oil lights, we were still running but low on power. Made it home and have checked the engine. Oil was down to the bottom mark on the dipstick, so it had used some. I noticed a drip of oil from the oir breather pipe - took off the air filter and found where about 1/4 litre of oil had gone.....into the airfilter/airbox. So I'm assuming crank case pressure has forced the oil in there.........so I need some bright ideas as to what the damage is and where I start looking please! I'm hold out a vain hope it might be simple, but I'm pretty sure you nice chappies here are going to tell me it's something nasty.........................just what I need the last 2 weeks have been crappy with my son being told he needs major spine surgery.
Cheers. Need to locate someone with a compression tester then. I was wondering if it might be something like a broken rocker arm/spring. Would that leave a valve open enough to pressurise the crankcase?
Square paper filter in a square plastic box - think it is a standard factory filter. No photos at the moment but I can get one tomorrow. Crankcase breather pipe goes into the side/back of the air box and was dripping oil and the bottom half of the paper filter is soaked in oil. The box was swimming in oil.
Have you pulled the little oil separator out of the airbox (where the breather hose connects) to see if it's bunged up?
Nope. I'll have a look at that tomorrow. Didn't even know there was one. Just thought the pipe simply connected onto breather box.
It does, but inside there's a little separator, like a tiny bottle brush. Worth making sure it (and the breather pipe) isn't bunged up.
As a quick test, pull the breather hose off, start the engine and hold your hand near the end. If you can feel just a gentle fluttering, that's normal. If you feel a good chuffing, may be blow-by from the pistons.
I think you may have a ring gone or melted piston if it's thrown that much oil out, how does it run, when was the last time you looked in the filter or topped the oil up ? I have a compression tester, I'm Using it on a van at the mo, if you wanna borrow it I need it back the same day
Out under the camper at 6.45am to work out what's wrong. Rocker covers off and I find loose metal rattling around inside the nearside one - never a good sign! One of the valves/springs looks dry as if the valves stuck open and exhaust gases have been blowing past. Inside of the rocker cover looks dry/heated at that point. Still can't work out where the metal has come from any ideas what it is? Front cylinder on nearside - is that number 3 exhaust valve? If so is it possible is just a kanckered pocker arm jamming something are are we talking a knackered head. They were new heads, not recon 6 yrs ago. Thanks for the offer of the compression tesser, but I'm not in a position to be able to get it back that quickly at the moment, so I'll ask around some local guys. Cheers anyway.
Looks like a bit of push rod, and could be the photo but does look like there's one missing? Inlet on 4
With the shape and colour I'd suspect that piece of metal is part of a valve guide. The way the spring is dry is indicative of the hot gasses seeping past the valve burning the oil off and this would pressurise the case greatly. They can move........trust me
Give the black bit that's dropped out a clean up with some sand paper, if it turns goldy coloured it's part of a valve guide
