Oil pressure relief valve

Message

cmdrew · #1 Post by **cmdrew** » Thu Jun 12, 2014 8:31 am

Another post in my engine replace story

Is there an oil pressure relief valve or similar anywhere on the Falco / RSV? I ask because I am finding that if I leave the bike overnight when I start it up first thing in the morning it rattles for a couple of seconds and then quietens down and sounds OK for a Rotax engine. Just seems like something is draining down over time and it's taking a little time to build oil pressure up again.

cmdrew · #2 Post by **cmdrew** » Thu Jun 12, 2014 2:36 pm

OK - ignore this - I spoke with Griff at Aprillia Performance and it seems likely that it is the hydraulic camchain tensioners which are at fault and it is chain rattle I am hearing. Unfortunately this means swapping the tensioners from my old engine into the new RSV one. Trouble is they are not that easy to get to so I am in the process of removing the throttle bodies again and probably the coolant manifold so that I can get to the tensioners to swap them over. Ho Hum...

At the same time I think I will start swapping casings over as the Falco had nice gray painted casings whereas the RSV lump just has plain castings.

Dalemac · #3 Post by **Dalemac** » Thu Jun 12, 2014 4:13 pm

cmdrew wrote:OK - ignore this - I spoke with Griff at Aprillia Performance and it seems likely that it is the hydraulic camchain tensioners which are at fault and it is chain rattle I am hearing. Unfortunately this means swapping the tensioners from my old engine into the new RSV one. Trouble is they are not that easy to get to so I am in the process of removing the throttle bodies again and probably the coolant manifold so that I can get to the tensioners to swap them over. Ho Hum...

At the same time I think I will start swapping casings over as the Falco had nice gray painted casings whereas the RSV lump just has plain castings.

Yup, hydraulic cam chain tensioners will rattle if they are not holding the pressure properly. This will be evident by hearing the cam chain rattle on startup and low down the rev range.

And yes, they are a bugger to get to. Tank off, airbox off, throttle bodies off. Drain coolant. You'll need some flexible socket joints and some extension bars to get to the tensioners.

I would highly recommend a new set of washers at the same time. When i replaced my tensioners the rear cylinder started to leak 2 years or so later. Probably not related, but well worth it considering the cost Vs nuisance balance of stripping it all back down again.

If you put brand new tensioners in, submerge the tensioners completely in oil and pump the piston to prime the tensioner before inserting it into the engine. Really doesn't sound nice without any oil in - trust me!

cmdrew · #4 Post by **cmdrew** » Thu Jun 12, 2014 9:01 pm

Well new tensioners in (or actually the ones from my Futura Engine!) and not as bad a job as I had expected. I found the key was to make space so I removed the coolant manifold as well as a few other coolant pipes so I had loads of access. B***dy tight though! The front cylinder tensioner was locked solid - I can't move it so I guess that's the culprit. Not had the chance to fire it up yet as I need to refill the coolant system again but I'm confident that there was a problem.

Really starting to learn how this bike goes together now which was much of the reason why I bought it in the first place...