Why does my diesel not rev when in gear?
Don't have a lot of experience w/diesel's but understand if they have fuel and air they'll run. My 1982 volvo/penta MD7B (2 cylinder/13HP) has gotten progressively harder (longer) to start over the last 3 yrs after setting for 1-2 weeks until the weekend use. (Think maybe I've been a bit impatient with it amd maybe have been flooding it trying to start). The fuel seems clean and I've changed filters regularly & used stabilizer additives over the winters and don't believe there's air in the fuel lines. Once started and warmed up it restarts quite easily. Doesn't seem to like to idle though and will sometimes die so either idle is too slow or something else.
Also, the engine will rev with throttle input while in neutral (although sometimes has quite a delay...if it were gas engine I'd say it was flooding/stumbling some with too much throttle input too fast). But sometimes when I put it in gear it will not rev at all with throttle input but just maintain idle (starting to do this more and more). When it does this I can sometimes nurse it to rev in neutral and then keeps the revs up slightly shifting into gear and it will have throttle response after that (try not to do this too much so I don't mess up tranny or shear the prop pin).
My batteries are starting to get a little weak (going on 5-6 yrs old) so it does turn a little slow but don't think that accounts for the lack of throttle response. Am hoping for something simple to get it more trustworthy (fun docking sometimes when the throttle doesn't respond) but may have to bite the bullet and get the mechanic to look at it ($$ouch).
Any usefull help would be appreciated...Thanks.
1982 Islander Bahama 30