New ENGINE

[paulob1]

Okay I have bought my engine and now have to go and collect it plus the cab for hesketh whop has bought a chassis without cab. I have beenn offered a chassis without engine and or cab and i am just contemplating whether to buy it...the new engine will put my truck back on the road, operational and ready to play, andy my new man will then spend the next few months sorting it out...he is thorough.

I hope to have the tatra running by the time of the forum meet

[Abrs]

Congrats Paul ;)

Just a quick vid here for you of the 19litere twin turbo unit I was talking about in the other thread, this ones actually out of an 815 but they were used in the last of the 813's. ;)

[youtube]http://www.youtube.com/watch?v=E_aHqmVgS5c[/youtube]

[paulob1]

hmm fitting a turbo to it doesnt seem like a problem at all, maybe that is the way to go with chassis two....for now i want bolt in up and running asap...likely i can get this old girl on the road for the forum meet if all goes well..

this is the info i have from czech republic about the tatra engine...> I dont know, where began this story about the engines for T-813, I heard it many times, but I dont undestand that. In past had Tatra T813 only one type of engine in 3 modification: T 930 31, T 930 33, T 930 37 and ther was the diefferences only in the system how to fit an air-filter and a clutch. It has 12V and 184 kw and no turbo (there was one military modification with one kirovecs turbo and it was made the RM-70 on the T813 undercart, but it is atypical and not standart engine); all other engines are from Tatra T-815.

[Abrs]

Trust me they were used wide scale in the 813 towards the end of production, have a look on the net, you're bound to even see a few examples for sale.

[Chris_CH]

There was a V12 17L fitted with a turbo, it was used in a train, this engine is on display at the Tatra museum in Koprivnice. I don't kwon if that engine was also fitted in a 813?

[paulob1]

am going with an 815 non turbo engine, it hs 315bhp some 60 more than the standard engine so should be fine. I am told that the gear train and chassis are not as strong as an 815 and so its a bit dodgy to fit the twin turbo engine...not sure I believe that...but given their thirst in normal format 315bhp may have twin effects, more modern engine, better efficiency and better fuel consumption...I hope..

[Chris_CH]

but given their thirst in normal format 315bhp may have twin effects, more modern engine, better efficiency and better fuel consumption...I hope..

I don't know what a 813 with the OEM engine is consuming but on mine I don't expect below 32l for 100 Km at legal speed (i.e. 90Km/h which give 1350 rpm on the engine).

Anyway I don't have a Tatra for its well known fuel efficiency....but for fun!!!!!

[paulob1]

got to agree, I dont own vehicles with fuel consumption down at 1 or 2 mpg just to worry about the fuel consumption although this month with the big hit in income at work I have to watch the pennies for a while and so will be unable to travel the countryside with gas guzzling trucks...

[duncan]

I don't know what a 813 with the OEM engine is consuming but on mine I don't expect below 32l for 100 Km at legal speed (i.e. 90Km/h which give 1350 rpm on the engine).

Im running the bog-standard 17.6 liter engine, and I averaged 47 liters per 100km over the last 8000km (which funny enough is exactly what the manual says it should do). This was mixed terrain and speed driving, asphalt, offroad, flat and mountains... we drove everywhere.

I'm still pondering about how to make it a tad more powerful though, its quite slow uphill, and when you put the trailer behind it's a fight to even get to 80 kmh at all. But there is no way I want to lose the air cooled v12, its reliable, easy to repair, and sounds awesome.

[Abrs]

Im running the bog-standard 17.6 liter engine, and I averaged 47 liters per 100km over the last 8000km (which funny enough is exactly what the manual says it should do). This was mixed terrain and speed driving, asphalt, offroad, flat and mountains... we drove everywhere.

That's still about £5K worth of diesel over here! But well done for putting some miles on the clock

Did you encounter any issues during that time? And what's your tyre wear like now?

I'm still pondering about how to make it a tad more powerful though, its quite slow uphill, and when you put the trailer behind it's a fight to even get to 80 kmh at all. But there is no way I want to lose the air cooled v12, its reliable, easy to repair, and sounds awesome.

Found that with mine, reminds me a lot of driving some of the old tractors, it seems to keep pulling but there's no real acceleration, I also found I was using the splitter an awful lot, could do with being an auto box - but I suppose for a truck of that era it's not too bad, I think sometimes we just forget how good more modern stuff really is.

Have you thought about perhaps adding turbos? I'm pretty sure these engines would stand it ok.

[haymish]

just put up a blurb that abrs maths out to find that mine was instead-so deleted it

[Abrs]

Haymish ya nob -Hehe ;) .....Fair does for admitting it though , I probably would have just edited the post and said something else completely

Yeah, works out at about £1 per mile, not bad really, only about the same as a Zil 131

[Chris_CH]

Have you thought about perhaps adding turbos? I'm pretty sure these engines would stand it ok.

What I have understood from Tatra mechanics is that the V12 17L could not be retrofit with turbos. As I said above one version of this engine has been designed with turbo, but this engines has modification on the lubrication system inside the engine.

I don't know if it could allows turbo but form the mechanics one on the side effect is a lot of heat below the piston which could melt down.

If really you want more HP I think it might be easier to retrofit a V12 19L next gen?

[Abrs]

You can fit a turbo to just about any engine if you really want to. I don't think heat is going to be a major problem with this lump, they don't run particularly hot anyway, and there are simple things you can do to combat it should it become a problem. Oil feed similarly shouldn't cause any major headaches, personally I would just go with using an external dry sump oil pump dedicated to just feeding the turbos, that eliminates any possible cause for concern. As far as the design goes both engines appear to be almost identical albeit apart from a few minor bolt on extras & slight modification to some of the castings, pistons etc don't seem to be any different, as don't most of the other major mechanical components as far as I can tell, I think it's more a case that the older engine was just never intended to be fitted with turbos hence it's missing some of the necessary bits n' bobs that are fitted to the later engines. I don't know if compression ratios are any different though, you'd need to check.

You could retro fit the later engine, but if you have a good one in already it's probably easier to mod it a bit. Another option is to replace the injector tips for the larger type (DOP 1598 IIRC), this will allow you to deliver more fuel quicker but it certainly won't do anything for your fuel economy

[Chris_CH]

Ok, this is just my 0.02 $ from what I have discussed with Tatra R&D engineers.

It might more change between the old T-930 and the later gene T3-930, the piston and the bottom part is different (not to mention bore/stroke) for the oil "path" (sorry I don't know the exact English term for that).

The compression ration is 16.5:1 this this is true for most of this generation diesel engine.

[Fastship]

Just remembered that Bulgarian dealer sells new 813 engines - £2.5k

[Chris_CH]

nice

[paulob1]

i would love a new engine...mine will get the 815 engine without turbo's

[Rob Reznik]

I've also seen them for sale where they are made in the Czech Republic.

[duncan]

Did you encounter any issues during that time? And what's your tyre wear like now?

I'm still pondering about how to make it a tad more powerful though, its quite slow uphill, and when you put the trailer behind it's a fight to even get to 80 kmh at all. But there is no way I want to lose the air cooled v12, its reliable, easy to repair, and sounds awesome.

Found that with mine, reminds me a lot of driving some of the old tractors, it seems to keep pulling but there's no real acceleration, I also found I was using the splitter an awful lot, could do with being an auto box - but I suppose for a truck of that era it's not too bad, I think sometimes we just forget how good more modern stuff really is.
Have you thought about perhaps adding turbos? I'm pretty sure these engines would stand it ok.

Dont get me wrong, I love driving it, it's hard work but satisfying My tires were pretty much slicks after the trip, but they were far from new to start with. I worked out that driving costs around 1 euro per KM, excluding tires. Had only 2 issues on the trip:

• A bolt keeping the clutch disengaging lever in place fell out, meaning the clutch pedal was useless. Managed to keep driving untill we found a gas station, quickly found cause, put everything back in place, secured bolts, drained air from clutch system, all fine. Left a big oil spot and angry gas station owner somewhere in the middle of poland.
• Engine stalled and would not start again, just off the highway in germany. Got friend to tow me to a quiet place (25km tow without powersteering, who needs a gym! took well over 2 hrs). Found out the bolt for "minimum position" on the injector pump fell out, allowing the throttle rack inside to slide out, misalign on all the individual injector pump units, and thus block itself. Cleaned everything, re-aligned, and hammered back together. Got us driving again, but on max half-throttle. Managed the last 300km home this way, and fixed properly.

On the last 6000km I did end up using/leaking around 160 litres of engine oil. Have changed a lot of seals since, but the engine still uses too much. To fix properly I need to remove the engine and take it apart completely. Since I dont want to be immobilized for months, I want to buy a new engine. Like Paul, I'm considering getting one of the T3-930 lumps. Found some of the 19 ltr bi-turbo ones for sale. Seeing as a new 813 engine costs around 2500 euro, and these big bi-turbo beasts go for around 5500, I think the lower oil and fuel consumption will pay back quickly.

Not going add turbos to the current engine, it would still need a lot of fixing to get the oil consumption down, plus it would require buying a new injection pump and 2 turbos, which makes it not all that much cheaper than a complete new engine.

Paul, any reason you want to get a non-turbo version? I havent decided yet, main requirement is that it has to be a tatra aircooled V12, but turbo or not Im not sure about. The turbos will lower the fuel consumption, and Im not buying the "the gearbox cannot take it" bit for one second. I have been inside the drivetrain 2 months ago when I replaced the differential and gearboxes, this is not kids-sized ;) As far as Im told, "normal" calculations are that a gearbox can take 60% more power than the engine delivers by default, as a safety margin. Should something in the drivetrain break, I will just fix it again Work on the inside of the tatra drivetrain really is not that difficult as the keyboard-warriors on the forums make it out to be.

Also, Im looking for some diagrams and sizes of the T3-930 engine, need to see if I have to modify the cabin to fit the lump. Any of you have some dimensions?

For the "pics or it didnt happen":