Honda Power Unit Hardware & Software

[Hoffman900]

Higher water content in E10?

Makes me think...

>Standard fuel pump
>Non-standard fuels
>Non-standard engine temperatures and vibrations

Then 3/4 of the Hondas are out of the race.

I dont think Gasly's breakdown was related to the fuel pump

The engines are very knock sensitive. Any fueling hiccup will burn up a piston / valve / etc. It is possible.

I don’t beleive Max’s issues were a fuel pump. That looked like a battery / deployment issue.

I am also surprised an engine fail would cause a lockup on Perez. I would think they have clutches like the MotoGP / Superbike / flat track guys have that cause the rear to freewheel in case of an engine stoppage.

I’d be more inclined to believe it is a spec fuel pump issue if we saw issues across multiple marques. I do worry it is a case of Christian publicly blaming a supplier to save face with investors.

[vorticism]

Isn't the fuel pump a standard component for all teams ?

I think the in-tank pump is, not sure about the one on the engine though.

Both the primer pump and the high pressure pump are classified SSC this year (standard supply component).

[Jaisonas]

I am also surprised an engine fail would cause a lockup on Perez. I would think they have clutches like the MotoGP / Superbike / flat track guys have that cause the rear to freewheel in case of an engine stoppage.

Perez was low rpm second gear on t1, an instant power cut will definitely cause you to spin. These cars are unmovable in gear without the engine.

[erikejw]

Both Max and Perez failure came quite soon after the safety car running long without proper cooling (due to low) speed.

An overheating problem?
Related to the mgu-K?

My first thought though was a software issue(bug) that started during the safety car period. Maybe a setting or to save fuel that was still active when the racing commenced. That they couldn't reverse.

[PhillipM]

Vibration does make more sense though. Is electric or engine driven?

Camshaft driven same as the hydraulic pump afaik. Seems there's still issues going on up there. There's more than one pump though, so depends which one.

[Hoffman900]

Vibration does make more sense though. Is electric or engine driven?

Camshaft driven same as the hydraulic pump afaik. Seems there's still issues going on up there. There's more than one pump though, so depends which one.

Electrical from the tank, mechanical off the cam for the TJI. Same as a DI set up.

I do love how I was voted negatively for my post. Probably by someone who couldn’t even explain why these engines are knock sensitive, or how a fuel pump failure could result in an issue and what those issues are, or the fuel pump configurations, etc. I do love how it was implied how I have an agenda. Been a Honda fan / user for 25 + years. Based on their complaint, I do suspect it’s a certain someone lurking

Judging by how each car failed, I do believe there may be a few separate issues and knowing the failure modes of a fuel pump, it’s why I am skeptical of that being the issue. It can be A issue, but I don’t believe it is the only issue.

[PhillipM]

Max and Perez's could be as simple as an air weep meaning the pumps started to cavitate once the fuel level got low. The AT looks like one of the high pressure pumps, either fuel or hydraulic, on the the end of the camshafts let go

[vorticism]

It seems they moved their oil reservoir this season, who knowns if that could contribute. In prev seasons there were pictures of it under the nose, above the t-tray, now that same area only looks to have electronics. So maybe a long shot but if they had a major repositioning of their oil reservoir perhaps that could be involved in the failure mode.

Wasn't Honda having an issue with McLaren back in 15/16 with how oil was getting starved due to how it was sloshing in the reservoir?

[mclaren_mircea]

On motorsport.it they say that an engineer from a team (but they dont say what team) are saying that the Honda engines got too hot and that caused a highes consumption of fuel. It is that the case I wont believe what Marko is saying that it is an easy fix. It is about packaging and the way the engine is working at the limit.

,,Tra qualche ingegnere di squadre avversarie c’è però un sospetto in merito alla causa che ha bloccato le due Red Bull, ed è un consumo anomalo di carburante. Non sarebbe imputabile ovviamente ad un ritmo di gara più intenso del previsto, ma ad un potenziale surriscaldamento che potrebbe aver alterato il consumo di benzina."

[Jaisonas]

Max and Perez's could be as simple as an air weep meaning the pumps started to cavitate once the fuel level got low. The AT looks like one of the high pressure pumps, either fuel or hydraulic, on the the end of the camshafts let go

AT was mgu-k

[saviour stivala]

These cars have an engine anti-stall system that involves opening the clutch when the car approaches zero speed. If the car is stopped and the engine also stopped and with transmission in gear (hydraulic pump not rotating) neutral can still be selected. By means of hydraulic pressure. As accumulator is still pressurized. The hydraulic pump is engine driven. Up to the 2.4l v8’s it used to be driven by the alternator shaft. Hydraulic tank is pressurized to avoid cavitation. The pressure system side includes an accumulator. 500 bar High pressure fuel pump is camshaft driven. Fuel is supplied to high pressure pump under low pressure by the pressurized fuel pod inside fuel tank. The fuel pod is low pressured by low pressure fuel pick-up pumps inside fuel tank.

[saviour stivala]

MV – ‘’There was no fuel coming to the engine and basically everything, just turned off. So I rolled back into the pit-lane’’.

Perez encountered the same problem which caused him to spin. The fuel supply to engine problem is believed to be due to either fuel lift-pumps or the pressurized fuel-pod or the E10 fuel itself (fuel temperature). With the brake and steering problem MV was still driving the car.

[Hoffman900]

I would have a real hard time believing the resin in the lift pump would break down with 5% more ethanol content. Everything in the US is E10 since they banned MTBE as an oxygenator and the fuel issues people had early on were due to it cleaning gunk out of the tank, not plastics. If they switched to E85 that would be a different story.

Heating of the fuel could be an issue, especially depending on packaging.

Vibrations inherent to the Honda could also cause the fuel lines / pumps / etc to go into resonance. This is far fetched but you can observe this with side draft carburetor engines. If you are brave, stand next to the engine on the dyno and you won’t be able to grab the float bowl. The carburetor bowl will resonate at such frequency at certain bad harmonics that the fuel foams. The lift pump pressure is probably nothing wild. I forget what the injector pressure has to be. I recently learned it’s 5000psi in DTM. I would have to think about this a little harder before I put any stock as an actual failure mode.

I am not shocked to learn teams in general struggled some with the switch, especially if they, like Honda, are using a hybrid HCCI / TJI combustion concept. I believe Honda only made this combustion concept work reliably by having a fuel developed especially for it. Otherwise it was inconsistent and more a happy accident than anything going by Wazari’s posts.

It is interesting that the RBR cars complained of decreasing power prior.
If fuel was falling off, then the engine would be derating itself, but this absolutely would have showed up along pit wall along with fuel pressure (I have no doubt that is sent to pit wall as well) and I believe would have resulted in a grenaded IC much more quickly.

Gasly’s failure was sudden, so that looks to be an entirely different issue and if that is the cam driven injector pump, that is a Honda part / design (which goes back to my one hypothesis about resonance) as that is directly bolted to the engine and not soft mounted like fuel lines should be.

[holeindalip]

I would have a real hard time believing the resin in the lift pump would break down with 5% more ethanol content. Everything in the US is E10 since they banned MTBE as an oxygenator and the fuel issues people had early on were due to it cleaning gunk out of the tank, not plastics. If they switched to E85 that would be a different story.

Heating of the fuel could be an issue, especially depending on packaging.

Vibrations inherent to the Honda could also cause the fuel lines / pumps / etc to go into resonance. This is far fetched but you can observe this with side draft carburetor engines. If you are brave, stand next to the engine on the dyno and you won’t be able to grab the float bowl. The carburetor bowl will resonate at such frequency at certain bad harmonics that the fuel foams. The lift pump pressure is probably nothing wild. I forget what the injector pressure has to be. I recently learned it’s 5000psi in DTM. I would have to think about this a little harder before I put any stock as an actual failure mode.

I am not shocked to learn teams in general struggled some with the switch, especially if they, like Honda, are using a hybrid HCCI / TJI combustion concept. I believe Honda only made this combustion concept work reliably by having a fuel developed especially for it. Otherwise it was inconsistent and more a happy accident than anything going by Wazari’s posts.

It is interesting that the RBR cars complained of decreasing power prior.
If fuel was falling off, then the engine would be derating itself, but this absolutely would have showed up along pit wall along with fuel pressure (I have no doubt that is sent to pit wall as well) and I believe would have resulted in a grenaded IC much more quickly.

Gasly’s failure was sudden, so that looks to be an entirely different issue and if that is the cam driven injector pump, that is a Honda part / design (which goes back to my one hypothesis about resonance) as that is directly bolted to the engine and not soft mounted like fuel lines should be.

I believe they can run them up to 7kpsi max on the hp pump…

[Hoffman900]

I would have a real hard time believing the resin in the lift pump would break down with 5% more ethanol content. Everything in the US is E10 since they banned MTBE as an oxygenator and the fuel issues people had early on were due to it cleaning gunk out of the tank, not plastics. If they switched to E85 that would be a different story.

Heating of the fuel could be an issue, especially depending on packaging.

Vibrations inherent to the Honda could also cause the fuel lines / pumps / etc to go into resonance. This is far fetched but you can observe this with side draft carburetor engines. If you are brave, stand next to the engine on the dyno and you won’t be able to grab the float bowl. The carburetor bowl will resonate at such frequency at certain bad harmonics that the fuel foams. The lift pump pressure is probably nothing wild. I forget what the injector pressure has to be. I recently learned it’s 5000psi in DTM. I would have to think about this a little harder before I put any stock as an actual failure mode.

I am not shocked to learn teams in general struggled some with the switch, especially if they, like Honda, are using a hybrid HCCI / TJI combustion concept. I believe Honda only made this combustion concept work reliably by having a fuel developed especially for it. Otherwise it was inconsistent and more a happy accident than anything going by Wazari’s posts.

It is interesting that the RBR cars complained of decreasing power prior.
If fuel was falling off, then the engine would be derating itself, but this absolutely would have showed up along pit wall along with fuel pressure (I have no doubt that is sent to pit wall as well) and I believe would have resulted in a grenaded IC much more quickly.

Gasly’s failure was sudden, so that looks to be an entirely different issue and if that is the cam driven injector pump, that is a Honda part / design (which goes back to my one hypothesis about resonance) as that is directly bolted to the engine and not soft mounted like fuel lines should be.

I believe they can run them up to 7kpsi max on the hp pump…

Got it. Thanks. Audi’s DTM pump is engineered to go to 7500psi if they need to, so likely similar. That engine does have some similarities to the F1 PU and I could see them adopting some of that knowledge if they ever wanted to join the party.

Watched The Race’s take on their issues. Reading between the lines it sounds like they may have ran out of fuel. Man, I hope they weren’t that silly.