20V Sauger Motor-Technik » Piston to bore clearance 7A.

Audi 5 Zylinder FORUM � 5 Zylinder Saug Motoren � 20V Sauger Motor-Technik � Piston to bore clearance 7A.

Themen-Einstellungen

Bereich wechseln

Nutzungsbedingungen & Rechtliches Board & Postingregeln Allgemeines Allgemeines Off Topic Vorstellungen Treffen Surf-Tipps 5 Zylinder Saug Motoren 20V Sauger Motor-Tuning 20V Sauger Motor-Technik 10V Sauger Motor Tuning 10V Sauger Motor-Technik 5 Zylinder Turbo Motoren 20V Turbo Motor-Tuning 20V Turbo Motor-Technik 10V Turbo Motor-Tuning 10V Turbo Motor-Technik Motorumbauten / Projekte 20V Sauger Motorumbauten Audi 5 Zylinder Motorumbauten Projekte Fahrzeug Technik Fahrwerk, Getriebe, Bremse, Lenkung, Abgasanlagen,... Elektrik & Car-HiFi Karosserie & Interior Klima Anleitungen / FAQ Test-Bereich Board Test Board Support Teilemarkt Alternative (Neu) Ersatzteilequellen Online Teilekatalog Vertrauensliste Teile-Suche Teile-Angebote

#1 | RE: Piston to bore clearance 7A. datum

22.11.2009 22:58

I bought myself an extra engine for my Coupe', i measured the pistons and the cilinder bore and so i came to the piston to bore clearance.
Cilinder 1 is 0.07mm (piston to bore)
Cilinder 2 is 0.06mm "
Cilinder 3 is 0.08mm "
Cilinder 4 is 0.07mm "
Cilinder 5 is 0.09mm "

According to my Haynes manual maximum is 0.08mm so nr. 5 is out of range.
I had the intention only renewing piston rings beqause new pistons are a bit expensive, what will happen if i put these pistons back in, they look okay and the cylinders are also in good shape.
Is it an option too put in an used piston in nr.5?

Antworten

#2 | RE: Piston to bore clearance 7A. datum

23.11.2009 20:13

using pistons with new rings in a old motor (not re-honed) is not good.
the bores should at least do be honed (not to be bored to the next repairing size), then you can use your old pistons with new rings.

But if the bores are out of range, i'd search a defect turbo-block from 3b, AAN, ABY or s.th. like that. they have a 81mm bore, and so you can bore and hone them to orginal 7A level, 82,51mm

Sommer: 1992er Audi 100 typ C4 mit 2,5L

Motor - Der Einzigartige
Winter: 1991er Audi 100 typ C4 mit AAR Motor
Frau: 1993er Audi 100 Avant mit 2,5er AAR Motor und MPI

Antworten

#3 | RE: Piston to bore clearance 7A. datum

23.11.2009 22:45

Why is hone so important, my cilinders are not out of range and they have the original grooves, it is the combination of piston and bore wich makes it that they are almost out of range.
Offcourse nr. 5 is allready out off range.

Antworten

#4 | RE: Piston to bore clearance 7A. datum

24.11.2009 19:53

are the pistons from the new motor or from another? if you'd mix a motor with used pistons from another motor and OLD rings, your motor will eat a lot of oil, and the compression will be bad.

same thing if you use new rings without a honing...

Sommer: 1992er Audi 100 typ C4 mit 2,5L

Motor - Der Einzigartige
Winter: 1991er Audi 100 typ C4 mit AAR Motor
Frau: 1993er Audi 100 Avant mit 2,5er AAR Motor und MPI

Antworten

#5 | RE: Piston to bore clearance 7A. datum

24.11.2009 22:34

No,no, the pistons ar originally from this motor, i put them back in the same cilinder, i think i am going to let the cilinders hone and than put them back in with new rings and see what happens, new pistons are out off budget.