Combines R70 losing power

Don't know about the R70 but we had problems with both a l2 and with a N7 losing power for no apparent reason. Turned out that the breather holes in the caps on the fuel tanks were getting plugged with dust. The l2 problem was fixed by dropping an empty tin over the cap to keep the dust off the lid and breather hole. The N7 was fixed by drilling out the breather hole to something over an 1_8". A folded rag to a couple of thicknesses was then placed over the cap and held there by a large O ring. No further problems after that crude but very satisfactory fix. That was our fix until we sold the combine some years later. Might be your problem. The fuel tank breather hole could be blocked. Cheers!

did you check to see if you were getting good fuel flow from the tankIJ I have had to blow the fuel line out backwards last year on my 62.

I would look at the main drive idler setup. Have seen too many that had the snubber set up wrong.........will do just what you describe......be good for a day or two and then start to loose power. There are nuts above the bracket on the draw bolt..........they should not be down against the bracket.......but several inches up. Just one more place too look...... The other place would be the throttle cable. Make sure you are going to the stop on the pump.

There is a one way check valve in fitting hooked to fuel hand pump. If chaff or something has got by water seperator filter it could lodge in this check. With this being blocked with a little trash it will not seal up which will cause a loss of fuel boost pressure. I will normally just pump hand pump fairly slow and listen for fuel charge valve to raddle a bit up at main fuel pump. If you have to pump rather fast to get valve to chatter you may well have trash in check valve. Good luck.

In these Deutz powered combines that have no turbo what is the engine power indicator monitoringIJ Is it this fuel boost pressureIJ Could a low power problem like this be diagnosed by looking at this gauge.

Well actually all Deutz powered machines have turbos except for R60s and first 1_2 year of R62s. The power monitor in Deutz powered machine was nothing more than a 300 RPM tach that reads from high idle down to 100 RPM below rated load (that is if set properly). On '92 and later machines (prior to Fieldstar info) you watch tack for rated RPM and when you lugged to rated RPM that was just simplily using the HP available. It could be engine is sick if reaching rated load to easily. Turbo boost gauge would be good indicator of HP on earlier machines prior to wastegate turbos but means little if machine has wastegate. Fuel boost would be fair way to judge HP on some engines but means nothing on others. Maybe the best way to gauge HP without dyno is turbo boost but you'ld have to bypass wastegate on machines equiped with such and then have a good guideline of what your engine produces for boost when working properly and even then turbo could be weak still allowing engine to develop full power. On the flip side turbo could be weak which would prevent engine ECM from allowing full fuel (tbran pointed this out to me that this could and has occured on the Cummins QSC). I don't know but there seems to be so many varibles that could affect a power meter (even the latest electronic monitors are counting on what the senders are telling it and then how the software interpets it ect.). Ah I'm getting to confused. Have a good one.

I am just familiar with the R-60 and really not that familiar with it.

Well, yesterday I was running a field that was making probably 110-120 bu per acre. I could only run 4.8 or so mph without losing rpms. The engine normally runs around 2400 rpm in the field. If I lug down to 2300 it will lose rpms even faster and then I have to slow down more. I hope I can find the problem because surely an R70 can handle 6 rows better than this.

Assuming you've checked all of the simple solutions such as fuel supply or restriction or air restriction you might want to consider removing the injection pump and checking governor. I used to have a R52 with Deutz and Robert Bosch pump that acted similar. The engine would hardly start the separator. Pulled the pump and the governor arm was worn unevenly and restricting the movement. It was like the metal was soft or not hardsurfaced. Replaced governor and engine ran fine with good power. This setup didn't have timing marks on pump so we used fingernail polish to make our own. Saved a lot of time when reinstalling pump.